1. A method comprising: iterating the steps of: receiving at a first system via a network interface from a remote system at least one term for use in searching of information, the at least one term for use in determining documents relating to the at least one term; providing search results within a search result set from the first system to the remote system, the search results including an indication of at least some of the documents relating to the at least one term, the search result set defining a resulting search space; providing at least one further term, the at least one further term provided for reducing the search results in the search result set by approximately 40%-60%, the at least one further term provided in dependence upon the at least one term and terms relating to documents within the search result set, the at least one further term relating to the resulting search space; wherein the resulting search space is reduced over an earlier search space by approximately two to the power of a number of terms selected since the earlier search space.