1. A method for processing structured search queries received at an internet search site from an affiliate or partner site, the method comprising: receiving at the internet search site a structured search query containing a user's search intent and other pertinent information from the affiliate or partner about the user and site, the structured search query being constructed as a conforming structured search string; parsing the structured search query based on a grammar published for affiliates or partners to construct the structured search query; extracting individual breadcrumbs from the structured search query that were used to build the structured search query, including decoding of position and meaning of each respective breadcrumb in the structured search query; forming match tokens from the identified individual breadcrumbs and combinations of breadcrumbs; matching listings stored in a search listing database with the formed match token strings; forming a search result list with the matched listings; and ranking elements of the search result list according to strength of match tokens to the original user search intent.