Add books. How can I narrow the search so that I get only paper books?

I have only printed books in my collections. So it would be helpful, it I didn't get audio books or ebooks in the search results. Sometimes the paper book is not among the search results because the non-paper books are listed before the printed ones.

This problem of course arises only when I don't have the correct ISBN.

Add the publisher information to the search. Chances are good that books published before ISBN did not have ebooks and audio books by the same publisher.

Also what sources are you using? OverCat is likely to have more paper books. Amazon is likely to have lots of Audio and e-books and general ratty data for older titles.

Manual entry is generally easier than editing lots of bad data.