diff --git a/core/src/server/grpc_impl/GrpcRequestHandler.cpp b/core/src/server/grpc_impl/GrpcRequestHandler.cpp
index 1d375a186b..a4ec05e8f9 100644
--- a/core/src/server/grpc_impl/GrpcRequestHandler.cpp
+++ b/core/src/server/grpc_impl/GrpcRequestHandler.cpp
@@ -521,9 +521,7 @@ GrpcRequestHandler::SearchInFiles(::grpc::ServerContext* context, const ::milvus
 
     // step 2: copy file id array
     std::vector<std::string> file_ids;
-    for (auto& file_id : request->file_id_array()) {
-        file_ids.emplace_back(file_id);
-    }
+    std::copy(request->file_id_array().begin(), request->file_id_array().end(), std::back_inserter(file_ids));
 
     // step 3: partition tags
     std::vector<std::string> partitions;