1. A method of identifying one or more particular media objects from a collection, comprising using a data processing system for: (a) indexing the collection to provide descriptors for each media object in the collection such that each media object is described by one or more of the descriptors; (b) receiving a query from a user specifying at least one keyword for a media object search, wherein the at least one keyword is not an image descriptor; (c) using the keyword(s) to search a second collection of tagged media objects to identify co-occurrence keywords; (d) using the identified co-occurrence keywords to provide an expanded list of keywords; (e) using the expanded list of keywords to search the descriptors to identify a set of candidate media objects satisfying the keywords; (f) grouping the set of candidate media objects according to at least one of the descriptors, and selecting one or more representative media objects from each grouping; and (g) displaying the representative media objects to the user.