1. A method of spoken document retrieval using multiple search transcription indices, the method comprising: receiving a query input formed of one or more query terms; for each query term determining a type of the query term, wherein a type includes a term in a speech recognition vocabulary or a term not in a speech recognition vocabulary; selecting one or more indices of search transcriptions for searching the query term based on the type of the query term; scoring the results from the one or more indices; and merging the results of the one or more indices for the query term.