diff --git a/src/test/java/de/ids_mannheim/korap/filter/TestKorapCollectionJSON.java b/src/test/java/de/ids_mannheim/korap/filter/TestKorapCollectionJSON.java
index 2d10b6f..bc8a5bb 100644
--- a/src/test/java/de/ids_mannheim/korap/filter/TestKorapCollectionJSON.java
+++ b/src/test/java/de/ids_mannheim/korap/filter/TestKorapCollectionJSON.java
@@ -18,8 +18,8 @@
 	KorapCollection kc = new KorapCollection(metaQuery);
 
 	assertEquals("filter with QueryWrapperFilter(+textClass:wissenschaft)", kc.getFilter(0).toString());
-	assertEquals("filter with QueryWrapperFilter(+pubPlace:Erfurt +author:Hesse)", kc.getFilter(1).toString());
-	assertEquals("extend with QueryWrapperFilter(+pubDate:[20110429 TO 20131231] +textClass:freizeit)", kc.getFilter(2).toString());
+	assertEquals("filter with QueryWrapperFilter(+(+pubPlace:Erfurt +author:Hesse))", kc.getFilter(1).toString());
+	assertEquals("extend with QueryWrapperFilter(+(+pubDate:[20110429 TO 20131231] +textClass:freizeit))", kc.getFilter(2).toString());
 	assertEquals(3, kc.getCount());
     };
 
@@ -29,7 +29,7 @@
 	String metaQuery = getString(getClass().getResource("/queries/metaquery2.jsonld").getFile());
 	KorapCollection kc = new KorapCollection(metaQuery);
 	assertEquals(1,kc.getCount());
-	assertEquals("filter with QueryWrapperFilter(+author:Hesse +pubDate:[0 TO 20131205])",kc.getFilter(0).toString());
+	assertEquals("filter with QueryWrapperFilter(+(+author:Hesse +pubDate:[0 TO 20131205]))",kc.getFilter(0).toString());
     };
 
     @Test
@@ -40,6 +40,16 @@
 	assertEquals("filter with QueryWrapperFilter(+pubDate:[20000101 TO 20131231])",kc.getFilter(0).toString());
     };
 
+    @Test
+    public void metaQuery7 () {
+	String metaQuery = getString(getClass().getResource("/queries/metaquery7.jsonld").getFile());
+	KorapCollection kc = new KorapCollection(metaQuery);
+	assertEquals(2,kc.getCount());
+	assertEquals("filter with QueryWrapperFilter(+(corpusID:c-1 corpusID:c-2))",kc.getFilter(0).toString());
+	assertEquals("filter with QueryWrapperFilter(+(+corpusID:d-1 +corpusID:d-2))",kc.getFilter(1).toString());
+    };
+
+
 
     public static String getString (String path) {
 	StringBuilder contentBuilder = new StringBuilder();
diff --git a/src/test/java/de/ids_mannheim/korap/filter/TestKorapFilter.java b/src/test/java/de/ids_mannheim/korap/filter/TestKorapFilter.java
index 661e45b..4651dbf 100644
--- a/src/test/java/de/ids_mannheim/korap/filter/TestKorapFilter.java
+++ b/src/test/java/de/ids_mannheim/korap/filter/TestKorapFilter.java
@@ -25,6 +25,8 @@
 	assertEquals("+textClass:tree +textClass:sport", kf.and("textClass","tree").and("textClass","sport").toString());
 	assertEquals("+textClass:tree +textClass:sport textClass:news", kf.and("textClass","tree").and("textClass","sport").or("textClass","news").toString());
 	assertEquals("+textClass:tree +textClass:sport +textClass:news", kf.and("textClass", "tree", "sport", "news").toString());
+
+	assertEquals("corpusID:c-1 corpusID:c-2 corpusID:c-3", kf.or("corpusID", "c-1", "c-2", "c-3").toString());
     };
 
     @Test
diff --git a/src/test/java/de/ids_mannheim/korap/index/TestRealIndex.java b/src/test/java/de/ids_mannheim/korap/index/TestRealIndex.java
index 3ac5a32..6be837f 100644
--- a/src/test/java/de/ids_mannheim/korap/index/TestRealIndex.java
+++ b/src/test/java/de/ids_mannheim/korap/index/TestRealIndex.java
@@ -12,6 +12,7 @@
 import org.apache.lucene.store.MMapDirectory;
 import de.ids_mannheim.korap.filter.BooleanFilter;
 import org.apache.lucene.search.spans.SpanQuery;
+import de.ids_mannheim.korap.util.QueryException;
 
 import static org.junit.Assert.*;
 import org.junit.Test;
diff --git a/src/test/java/de/ids_mannheim/korap/search/TestKorapSearch.java b/src/test/java/de/ids_mannheim/korap/search/TestKorapSearch.java
index 9b5be8b..ecbf426 100644
--- a/src/test/java/de/ids_mannheim/korap/search/TestKorapSearch.java
+++ b/src/test/java/de/ids_mannheim/korap/search/TestKorapSearch.java
@@ -279,6 +279,69 @@
 
     };
 
+    @Test
+    public void searchJSONCollection () throws IOException {
+
+	// Construct index
+	KorapIndex ki = new KorapIndex();
+	// Indexing test files
+	for (String i : new String[] {"00001", "00002", "00003", "00004", "00005", "00006", "02439"}) {
+	    ki.addDocFile(
+	      getClass().getResource("/wiki/" + i + ".json.gz").getFile(), true
+            );
+	};
+	ki.commit();
+
+	String json = getString(getClass().getResource("/queries/metaquery8-nocollection.jsonld").getFile());
+	
+	KorapSearch ks = new KorapSearch(json);
+	KorapResult kr = ks.run(ki);
+	assertEquals(276, kr.getTotalResults());
+	assertEquals(0, kr.getStartIndex());
+	assertEquals(10, kr.getItemsPerPage());
+
+	json = getString(getClass().getResource("/queries/metaquery8.jsonld").getFile());
+	
+	ks = new KorapSearch(json);
+	kr = ks.run(ki);
+
+	assertEquals(147, kr.getTotalResults());
+	assertEquals("WPD_AAA.00001", kr.getMatch(0).getDocID());
+	assertEquals(0, kr.getStartIndex());
+	assertEquals(10, kr.getItemsPerPage());
+
+	json = getString(getClass().getResource("/queries/metaquery8-filtered.jsonld").getFile());
+	
+	ks = new KorapSearch(json);
+	kr = ks.run(ki);
+
+	assertEquals(28, kr.getTotalResults());
+	assertEquals("WPD_AAA.00002", kr.getMatch(0).getDocID());
+	assertEquals(0, kr.getStartIndex());
+	assertEquals(10, kr.getItemsPerPage());
+
+	json = getString(getClass().getResource("/queries/metaquery8-filtered-further.jsonld").getFile());
+	
+	ks = new KorapSearch(json);
+	kr = ks.run(ki);
+
+	assertEquals(0, kr.getTotalResults());
+	assertEquals(0, kr.getStartIndex());
+	assertEquals(10, kr.getItemsPerPage());
+
+	json = getString(getClass().getResource("/queries/metaquery8-filtered-nested.jsonld").getFile());
+	
+	ks = new KorapSearch(json);
+	kr = ks.run(ki);
+
+	assertEquals("filter with QueryWrapperFilter(+(ID:WPD_AAA.00003 (+tokens:s:die +tokens:s:Schriftzeichen)))", ks.getCollection().getFilter(1).toString());
+
+	assertEquals(119, kr.getTotalResults());
+	assertEquals(0, kr.getStartIndex());
+	assertEquals(10, kr.getItemsPerPage());
+
+    };
+
 
     public static String getString (String path) {
 	StringBuilder contentBuilder = new StringBuilder();
diff --git a/src/test/resources/queries/metaquery7.jsonld b/src/test/resources/queries/metaquery7.jsonld
new file mode 100644
index 0000000..a7114e6
--- /dev/null
+++ b/src/test/resources/queries/metaquery7.jsonld
@@ -0,0 +1,60 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "meta":{
+	"startPage" : 1,
+	"count" : 5,
+	"context" : {
+	    "left" : [ "token", 3 ],
+	    "right" : [ "char", 6 ]
+	}
+    },
+    "query":{
+	"@type":"korap:token",
+	"wrap":{
+	    "@type":"korap:term",
+	    "foundry":"mate",
+	    "layer":"l",
+	    "key":"lediglich"
+	}
+    },
+    "collections": [
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#corpusID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "c-1"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "c-2"
+		    }
+		]
+	    }
+	},
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "and",
+		"@field": "korap:field#corpusID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "d-1"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "d-2"
+		    }
+		]
+	    }
+	}
+    ]
+}
diff --git a/src/test/resources/queries/metaquery8-filtered-further.jsonld b/src/test/resources/queries/metaquery8-filtered-further.jsonld
new file mode 100644
index 0000000..945a2fa
--- /dev/null
+++ b/src/test/resources/queries/metaquery8-filtered-further.jsonld
@@ -0,0 +1,80 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "query": {
+	"@type": "korap:token", 
+	"wrap": {
+	    "@type": "korap:term", 
+	    "foundry": "mate",
+	    "layer" : "lemma",
+	    "key":"der", 
+	    "match": "match:eq"
+	}
+    },
+    "meta":{
+	"startPage":1,
+	"count": 10,
+	"context":{
+	    "left":["char",90],
+	    "right":["char",90]
+	}
+    },
+    "collections": [
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00001"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	},
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00003"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	},
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00001"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00005"
+		    }
+		]
+	    }
+	}
+    ]
+}
diff --git a/src/test/resources/queries/metaquery8-filtered-nested.jsonld b/src/test/resources/queries/metaquery8-filtered-nested.jsonld
new file mode 100644
index 0000000..ebb56ab
--- /dev/null
+++ b/src/test/resources/queries/metaquery8-filtered-nested.jsonld
@@ -0,0 +1,73 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "query": {
+	"@type": "korap:token", 
+	"wrap": {
+	    "@type": "korap:term", 
+	    "foundry": "mate",
+	    "layer" : "lemma",
+	    "key":"der", 
+	    "match": "match:eq"
+	}
+    },
+    "meta":{
+	"startPage":1,
+	"count": 10,
+	"context":{
+	    "left":["char",90],
+	    "right":["char",90]
+	}
+    },
+    "collections": [
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00001"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	},
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00003"
+		    },
+		    {
+			"@type": "korap:group",
+			"relation": "and",
+			"@field": "korap:field#tokens",
+			"operands": [
+			    {
+				"@type": "korap:term",
+				"@value": "s:die"
+			    },
+			    {
+				"@type": "korap:term",
+				"@value": "s:Schriftzeichen"
+			    }
+
+			]
+		    }
+		]
+	    }
+	}
+    ]
+}
diff --git a/src/test/resources/queries/metaquery8-filtered.jsonld b/src/test/resources/queries/metaquery8-filtered.jsonld
new file mode 100644
index 0000000..ddb51cf
--- /dev/null
+++ b/src/test/resources/queries/metaquery8-filtered.jsonld
@@ -0,0 +1,61 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "query": {
+	"@type": "korap:token", 
+	"wrap": {
+	    "@type": "korap:term", 
+	    "foundry": "mate",
+	    "layer" : "lemma",
+	    "key":"der", 
+	    "match": "match:eq"
+	}
+    },
+    "meta":{
+	"startPage":1,
+	"count": 10,
+	"context":{
+	    "left":["char",90],
+	    "right":["char",90]
+	}
+    },
+    "collections": [
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00001"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	},
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00003"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	}
+    ]
+}
diff --git a/src/test/resources/queries/metaquery8-nocollection.jsonld b/src/test/resources/queries/metaquery8-nocollection.jsonld
new file mode 100644
index 0000000..6edf506
--- /dev/null
+++ b/src/test/resources/queries/metaquery8-nocollection.jsonld
@@ -0,0 +1,21 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "query": {
+	"@type": "korap:token", 
+	"wrap": {
+	    "@type": "korap:term", 
+	    "foundry": "mate",
+	    "layer" : "lemma",
+	    "key":"der", 
+	    "match": "match:eq"
+	}
+    },
+    "meta":{
+	"startPage":1,
+	"count": 10,
+	"context":{
+	    "left":["char",90],
+	    "right":["char",90]
+	}
+    }
+}
diff --git a/src/test/resources/queries/metaquery8.jsonld b/src/test/resources/queries/metaquery8.jsonld
new file mode 100644
index 0000000..77dfc4c
--- /dev/null
+++ b/src/test/resources/queries/metaquery8.jsonld
@@ -0,0 +1,42 @@
+{
+    "@context": "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld",
+    "query": {
+	"@type": "korap:token", 
+	"wrap": {
+	    "@type": "korap:term", 
+	    "foundry": "mate",
+	    "layer" : "lemma",
+	    "key":"der", 
+	    "match": "match:eq"
+	}
+    },
+    "meta":{
+	"startPage":1,
+	"count": 10,
+	"context":{
+	    "left":["char",90],
+	    "right":["char",90]
+	}
+    },
+    "collections": [
+	{
+	    "@type": "korap:meta-filter",
+	    "@id": "korap-filter#id-1223232",
+	    "@value": {
+		"@type": "korap:group",
+		"relation": "or",
+		"@field": "korap:field#ID",
+		"operands": [
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00001"
+		    },
+		    {
+			"@type": "korap:term",
+			"@value": "WPD_AAA.00002"
+		    }
+		]
+	    }
+	}
+    ]
+}