1. A method of processing a search request received from a user, the search request directed at identifying a desired item from a set of items, in which the identification is based on comparing a topic of the search request to previous user input, the method comprising: providing access to a set of content items, each of the content items being associated with metadata that describes the corresponding content items; providing information about at least one search previously received from a user; receiving a present input from the user, the present input intended by the user to identify a desired content item; determining a measure of relatedness between the information about the at least one previous search and an element of the present input; upon a condition in which the relatedness measure does not exceed a threshold value, selecting a subset of content items based on comparing the present input with the metadata that describes the subset of content items; and upon a condition in which the relatedness measure exceeds the threshold value, selecting a subset of content items based on comparing the present input and information about the at least one previous search with the metadata that describes the subset of content items.