Fix chunk enable/disable issue (#3579)

### What problem does this PR solve?

#3576

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

rag/nlp/search.py

@@ -56,7 +56,7 @@ class Dealer:
             if key in req and req[key] is not None:
                 condition[field] = req[key]
         # TODO(yzc): `available_int` is nullable however infinity doesn't support nullable columns.
-        for key in ["knowledge_graph_kwd"]:
+        for key in ["knowledge_graph_kwd", "available_int"]:
             if key in req and req[key] is not None:
                 condition[key] = req[key]
         return condition