4. The method of claim 1 , further comprising: storing in the data storage device a user profile with information selected from the group consisting of: the user's demographic information, one or more query words the user entered before, one or more results the user clicked on before, and weights for symbol pairs obtained in the user's previous searches.
4. The method of claim 1 , further comprising: storing in the data storage device a user profile with information selected from the group consisting of: the user's demographic information, one or more query words the user entered before, one or more results the user clicked on before, and weights for symbol pairs obtained in the user's previous searches. 5. The method of claim 4 , further comprising: augmenting the query by using information from the user profile.