1. Using a computer system with access to electronically retrievable content in digital form, a method of determining presentations from a set of presentations to present alongside search results, the method comprising: receiving a request from a user in the form of a search query string; canonicalizing one or more terms in the search query string to form a reformed search query string when the one or more terms meet canonicalization criteria; applying the reformed search query string as an input to a presentation processor; selecting, using the presentation processor, presentations to be included in the response to the request, wherein selection of presentations is done according to at least keywords associated with presentations in the set of presentations, further wherein at least one keyword is a canonicalization of at least one of the one or more terms meeting the canonicalization criteria.