Fiction AND Non Fiction

Give this a shot:
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• BibRec - Fiction - Equals - Yes
• Heading - Type - Begins - Subj
• Heading - Code - In - 900,900W,970,970NA

For the list in the last line, include whatever common non-fiction subjects you want to check. I pulled your subject codes for History & Geography, History - World, History - North America, and History - Native American, and got 87 hits. Once you're in the query set, you can use the Next button to browse through the records and determine whether the fiction box needs to be un-marked, or if the non-fiction subjects should be removed. 

And of course, you can also reverse the query, searching for Fiction = No, and listing some common fiction codes (Fiction, Literature, Historical Fiction, Mystery, and Bestseller Fiction might be a good start).