def _retrieve(
        self,
        query_bundle: QueryBundle,
        **kwargs: Any,
    ) -> List[NodeWithScore]:
        """
        Retrieve top k most similar nodes.

        Args:
            query_bundle: Query Bundle

        """
        return self._vectara_query(query_bundle, **kwargs)[0]  # return top_nodes only

        Retrieve top k most similar nodes.

        Args:
            query_bundle: Query Bundle

        
llama-index-integrations/indices/llama-index-indices-managed-vectara/llama_index/indices/managed/vectara/retriever.py