FTS on JOIN in CBL

Is there any way to do a full text search on a JOIN statement? Or is FTS limited to operating on single documents only?

Essentially, I have a 1:M relationship, and I want to perform an FTS on the documents on the “many” side, but still search keywords in documents referenced (via foreign key) by the documents on the “many” side.
For example, consider contract documents that reference involved organization documents. I’d like to FTS through the contracts using the names of the involved organizations in addition to information found in the contract documents.