The solution to this problem would be to assign a Dewey Decimal mumber to each book and then permit searches by Dewey numbers. With so many books already in the collection, it may be impossible to do anything at this point as it would mean countless hours of work reorganizing. It's hard to believe that a library such as BookShare wasn't originally organized using some sort of accepted cataloging system. At this stage, we may be talking about an impracticality.