Libertyuk,
I've run into this problem before and had commented in another thread:
http://amanita-design.net/forum/index.php?/topic=4643.0.html...if that helps at all to look at that thread.
But, like I'd mentioned then, basically, my advice if that's happening is to leave the book, do something else (like grab one of the other wrenches or walk around a little) and then walk back to it and try again; and you might have to do that a couple of times.