A computer-implemented method for processing documents in a multi-lingual document database includes generating an initial ranking of retrieved multi-lingual documents using an information retrieval system and based upon a user search query, and processing vocabulary words based upon occurrences thereof in at least some of the retrieved multi-lingual documents. Respective relevancies of the vocabulary words based on the occurrences thereof and the user search query are generated. A re-ranking of the retrieved multi-lingual documents is generated based on the relevancies of the vocabulary words.