When searching for items in the Family History Library card catalog, consider searching for all levels. Recently I was looking for some township land records that had been transcribed for a certain township in Ontario. The website indicated the Family History Library had them yet no amount of searching in the records at the county level located them.
That's because the township land records I needed were in the card catalog under Ontario the province and not under any specific county.
When searching the FamilyHistory card catalog--don't just focus on the county. Try other political levels such as the town, state, etc.