Just need to try it again

Even if you think you’ve tried it, try it again. I can’t remember the number of times that someone has told me they had “searched for that,” “tried that,” etc. with no luck. And when we did it together, the result was found.

No guarantees, but maybe you need to try researching something again. It is always possible to overlook something the first time or not to search in the way you thought you did.