Keep on going, and the chances are that you will stumble on something, perhaps when you are least expecting it. I never heard of anyone ever stumbling on something sitting down.
Virtually nothing comes out right the first time. Failures, repeated failures, are finger posts on the road to achievement. The only time you don't want to fail is the last time you try something.... One fails forward toward success.
We need to teach a highly educated person that it is not a disgrace to fail and that he must analyze every failure to find its cause. He must learn how to fail intelligently, for failing is one of the greatest arts of the world.