I looked in the forum before posting to see if someone had already signaled this: either in EYB Library or one's own, either on iPad or desktop, when Unindexed Books button is selected, Indexed Books buttons also checks. The resulting search gives the unindexed books in either library but when one tries to refine the search by selecting a bookmark, result returns a zero (which is logical). There is no way to clear the Indexed Books button without returning to a global search without the bookmark refinement. I hope what I wrote is clear enough for you to understand the issue!