Abstract: A computer-implemented method performed at a server system for enhancing search queries received from client devices. The method comprises maintaining a dataset mapping a co-appearance prevalence of at least two attribute values of each of a plurality of attributes of each of a plurality of product categories in a plurality search queries submitted to a search engine and during a single search thread, receiving at the server system a plurality of evolving search phrases from a search requestor at a client device that is distinct from the server system.