The Multilingual Semantic Search Assistant (MSSA) was developed to help users search the FAO AGRIS/CARIS Network more effectively. MSSA integrates four key functions - helping users find proper keywords, browse indexed topics to find keywords, expand queries across multiple languages, and expand queries using synonyms. These functions draw from the AGROVOC thesaurus to assist users in formulating semantic queries without requiring any changes to the underlying search engine. An initial evaluation found that expanding queries across languages using MSSA retrieved more relevant documents.