A method for improving searches in a peer-to-peer (P2P) file sharing
system that includes a plurality of server computers. A content file,
identified by a descriptor including at least one metadata term and a
mathematical identifier that uniquely identifies the content file in one
of the server computers, is selected for searching. Other server
computers are searched to find one or more matching content files; one
that has a descriptor with a mathematical identifier matching the
mathematical identifier of the first content file. The descriptors of the
matching content files are returned to the searching server computer and
used to expand the local descriptor.