Remember, search engines are your best friend, but to get a good answer, you need to ask a good question.
If you're running out of ideas, explain the problem to someone else. If there's a flaw in your logic or another way to tackle the problem you may well see it even before you finish the explanation, and even if your audience didn't understand a word you said or only asked silly questions!
Creep up on a problem from every possible angle. Sooner or later, with luck, you'll catch it out.