Force exact match from postgres ts_query
As filiprem says, you can combine the match and the equality by an AND.  It will use the FTS index to get candidates and then just filter out the ones that it needs to for the equality

But you can also build a regular index on 'journal_name' and then just write the query naturally. The 2nd index will take some maintenance overhead, but less than the index your already have does.  If you do this type of query a lot, you should probably add the extra index.