Private query brings new challenges to the design of Database Management System (DBMS). A recent work of Blind Seer system introduces a new setup which has an efficient sublinear search for arbitrary boolean query. It splits an index server from server such that client can communicate with index server to retrieve encrypted records. During the query, the server learns nothing about the query.

The original system requires the server to stay online to wait for the client to request for the decryption key. In this work, we design a new protocol for client only communicate with the index server. In addition, the communication rounds between client and index server in the original protocol are linear to the depth of search tree. In our protocol, we show how to reduce it to constant rounds.