A retrieval method on a database of documents including text and names of participants associated with the documents includes: receiving a text query facet of keywords and a persons query facet of participant names; computing an enriched text query as an aggregation of the text query facet, a monomodal expansion of the text query facet based on the keywords, a cross-modal expansion of the text query facet based on the participant names, and a topic expansion of the text query facet based on a topic model associating words and topics; computing an enriched persons query as an aggregation of the persons query facet, a monomodal expansion of the persons query facet based on the participant names, a cross-modal expansion of the persons query facet based on the keywords, and a community expansion of the persons query facet based on a community model associating persons and communities.