Have you ever lost something? Then you tried hard to search for it, but you found that no where to be found? Well, I think everybody must have this kind of feeling before. When your mind is scattered, you can't focus on what you are doing. You'll feel very vexed at that time.
When this situation occurs, try to calm down yourself and do other things first. When there is nothing to do to solve it, you should ask yourself why you are so tiring searching. In fact, you can't find that thing with such mind condition. Perhaps, you need to let it go for a while. Take a glass of water, and then try to recall if you are searching for it. In this way, you are probably able to find it.
If it refers to a problem not about finding a thing, searching for the solution also needs a focused mind, not a scattered mind. Doing other things, which give your mind more relaxing space, will sometimes do good and perhaps solution will strike your mind. Just try your best, but not forcing it. Life is about using a focused mind. It's easier said than done, though...