[Earthlark]

I'm using the Calibre plugin Quality Check to search books in my library. I'd like to be able to find words related to specific contexts within a book, probably searching the whole book for two or more words appearing in either a single sentence or a paragraph (possibly a section) in any order. For example, if I'm searching for "protein" as it relates to "batter", I'd like to be able to search the book for those two terms without getting results for protein as it relates to meat, nuts, etc.

I've played around with the regex for this a bit, but can't seem to get it, and my regex skills still fairly limited, so I'd really appreciate some help on this.

Or, is there another program or plugin more suited to this task? Cheers!