1. In a computing environment, a method comprising: determining similarity between a first document of a first language and a second document of a second, different language; ranking, by a Boltzmann machine, relevance of the second document with respect to a query submitted in the first language using the similarity determined; and displaying a result set according to the relevance in response to the query submitted in the first language, wherein the result set includes at least the second document of the second, different language.