fix knn combined query

Author: Samiul-TheSoccerFan

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/queries/SemanticKnnVectorQueryRewriteInterceptor.java

@@ -52,16 +52,20 @@ protected QueryBuilder buildInferenceQuery(QueryBuilder queryBuilder, InferenceI
         assert (queryBuilder instanceof KnnVectorQueryBuilder);
         KnnVectorQueryBuilder knnVectorQueryBuilder = (KnnVectorQueryBuilder) queryBuilder;
         Map<String, List<String>> inferenceIdsIndices = indexInformation.getInferenceIdsIndices();
+        QueryBuilder finalQueryBuilder;
         if (inferenceIdsIndices.size() == 1) {
             // Simple case, everything uses the same inference ID
             Map.Entry<String, List<String>> inferenceIdIndex = inferenceIdsIndices.entrySet().iterator().next();
             String searchInferenceId = inferenceIdIndex.getKey();
             List<String> indices = inferenceIdIndex.getValue();
-            return buildNestedQueryFromKnnVectorQuery(knnVectorQueryBuilder, indices, searchInferenceId);
+            finalQueryBuilder = buildNestedQueryFromKnnVectorQuery(knnVectorQueryBuilder, indices, searchInferenceId);
         } else {
             // Multiple inference IDs, construct a boolean query
-            return buildInferenceQueryWithMultipleInferenceIds(knnVectorQueryBuilder, inferenceIdsIndices);
+            finalQueryBuilder = buildInferenceQueryWithMultipleInferenceIds(knnVectorQueryBuilder, inferenceIdsIndices);
         }
+        finalQueryBuilder.boost(queryBuilder.boost());
+        finalQueryBuilder.queryName(queryBuilder.queryName());
+        return finalQueryBuilder;
     }
 
     private QueryBuilder buildInferenceQueryWithMultipleInferenceIds(
@@ -102,6 +106,8 @@ protected QueryBuilder buildCombinedInferenceAndNonInferenceQuery(
                 )
             );
         }
+        boolQueryBuilder.boost(queryBuilder.boost());
+        boolQueryBuilder.queryName(queryBuilder.queryName());
         return boolQueryBuilder;
     }
 
@@ -124,7 +130,7 @@ private QueryBuilder buildNestedQueryFromKnnVectorQuery(
                 queryVectorBuilder
             ),
             ScoreMode.Max
-        ).queryName(knnVectorQueryBuilder.queryName()).boost(knnVectorQueryBuilder.boost());
+        );
     }
 
     private KnnVectorQueryBuilder addIndexFilterToKnnVectorQuery(Collection<String> indices, KnnVectorQueryBuilder original) {