1. A method for performing mobile search utilizing a plurality of member engines, comprising: receiving a search request by a search server, wherein the search request carries: keyword information to be searched for, and an instant interest model of a user associated with the search request and a long-term interest model of the user which are acquired by a search application server, wherein: the instant interest model of the user is an instant interest model vector formed by score values of N dimensions, wherein: the score value of each of the N dimensions indicates an interest level of the user on said each of the N dimensions, and is calculated according to relevant data of a query sequence q(1), . . . , q(t-1), q(t) in a same search context session initiated by the user, wherein: the same search context session corresponds to the search request, and the search context session comprises a sum of a period of preset time before the current query q(t) occurs and a time when the current query q(t) occurs; calculating by the search server, a relevance score value of each member engine utilizing: the search request, meta index information describing stored contents of the member engine, the instant interest model of the user, and the long-term interest model of the user; and selecting by the search server, one or more member engines to search for the keyword information according to the relevance score value.
2. The method for mobile search according to claim 1 , wherein the long-term interest model is a long-term interest model vector formed by score values of N dimensions, and the score value of each of the dimensions is calculated according to search history data and a static profile of a user.