In a system where a search query based on a partially formed query expression can be sent in a request to a server before the user finishes inputting the entire query expression, an intelligent mechanism is provided at a client of the server to prevent too many unnecessary requests from being sent to the server. In response to receiving, at the client, user input, the intelligent mechanism may determine whether a corresponding search query matches a key in the local search result cache. If so, local search results are displayed to the user. In addition, a timer may be used to delay sending the request to the server.