This is a great question, and one which i’m sure is possible, but one that I have no idea how.
My first though is one which has 2 parts:
1. Filter query
If you searched for ‘Elliot Condon’, find the post with this title (the bio post). Now you have an id of 123. Use this ID to modify the search parameter so that your search is for 123 (maybe you can target this as a meta_query only?).
This should hopefully find books that have an author of 123.
2. Filter the results
If the above query works, then you can swap out ‘123’ for ‘Elliot Condon’ and your results should read correctly.
This will be pretty complex and will require a lot of debugging and searching through source code, but it’s worth a shot.
Also, I would ask the guys over at Relevanssi what their thoughts are.
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