16. One or more computer storage media having computer-executable instructions stored thereon, which in response to execution by a computer, cause the computer to perform steps comprising: featurizing a set of documents of different languages into multilingual features; clustering the set of documents into topic-based clustering data using the multilingual features: constructing a Boltzmann machine based on the documents, the multilingual features of the documents, and the topic-based clustering data; using the Boltzmann machine to rank the set of documents of different languages returned in a search; and displaying at least a portion of the set of documents, wherein an order to display the portion of the set of documents is based at least in part on the rank generated by the Boltzmann machine.
18. The one or more computer storage media of claim 16 wherein constructing the Boltzmann machine comprises having each document represented as a document unit corresponding to that document's features, having each cluster represented as a cluster unit, and having edges between each document unit and each cluster unit represent a correlation between that document's relevancy and that cluster's relevancy.