diff --git a/src/main/java/it/cavallium/dbengine/database/disk/LLLocalMultiLuceneIndex.java b/src/main/java/it/cavallium/dbengine/database/disk/LLLocalMultiLuceneIndex.java
index d837e8c..0f222c5 100644
--- a/src/main/java/it/cavallium/dbengine/database/disk/LLLocalMultiLuceneIndex.java
+++ b/src/main/java/it/cavallium/dbengine/database/disk/LLLocalMultiLuceneIndex.java
@@ -17,7 +17,6 @@ import java.nio.file.Path;
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.atomic.AtomicLong;
@@ -26,8 +25,10 @@ import org.warp.commonutils.batch.ParallelUtils;
 import org.warp.commonutils.functional.IOBiConsumer;
 import org.warp.commonutils.functional.TriFunction;
 import reactor.core.publisher.Flux;
+import reactor.core.publisher.GroupedFlux;
 import reactor.core.publisher.Mono;
 import reactor.core.scheduler.Schedulers;
+import reactor.util.function.Tuple2;
 import reactor.util.function.Tuples;
 
 public class LLLocalMultiLuceneIndex implements LLLuceneIndex {
@@ -88,8 +89,8 @@ public class LLLocalMultiLuceneIndex implements LLLuceneIndex {
 	}
 
 	@Override
-	public Mono<Void> addDocuments(Iterable<LLTerm> keys, Iterable<LLDocument> documents) {
-		return runPerInstance(keys, documents, LLLuceneIndex::addDocuments);
+	public Mono<Void> addDocuments(Flux<GroupedFlux<LLTerm, LLDocument>> documents) {
+		return documents.flatMap(docs -> getLuceneIndex(docs.key()).addDocuments(documents)).then();
 	}
 
 	private Mono<Void> runPerInstance(Iterable<LLTerm> keys,
@@ -131,8 +132,8 @@ public class LLLocalMultiLuceneIndex implements LLLuceneIndex {
 	}
 
 	@Override
-	public Mono<Void> updateDocuments(Iterable<LLTerm> keys, Iterable<LLDocument> documents) {
-		return runPerInstance(keys, documents, LLLuceneIndex::updateDocuments);
+	public Mono<Void> updateDocuments(Flux<GroupedFlux<LLTerm, LLDocument>> documents) {
+		return documents.flatMap(docs -> getLuceneIndex(docs.key()).updateDocuments(documents)).then();
 	}
 
 	@Override
@@ -153,7 +154,7 @@ public class LLLocalMultiLuceneIndex implements LLLuceneIndex {
 
 	@Override
 	public Mono<LLSearchResult> moreLikeThis(@Nullable LLSnapshot snapshot,
-			Map<String, Set<String>> mltDocumentFields,
+			Flux<Tuple2<String, Set<String>>> mltDocumentFields,
 			int limit,
 			String keyFieldName) {
 		return Flux