So, you're saying that you'll search and find a resource one time but OLLY won't add it, and then next time you search and find the exact same resource and OLLY will add it?
OLLY uses the Google book search for this feature, so sometimes it will turn up a huge list of titles from different publishers, years, editions, etc. (especially with fiction). Some out-of-print items may not have much metadata at all to add. So, I was wondering if maybe some of the items you are adding to your library are harder to retrieve . . .