What should I be taking while trying to conceive??

What vitamins do I need to be taking while trying to conceive? And any other tips you have! My husband and I have been trying, but only started a couple of months ago tracking everything. I was in a previous marriage and conceived while on birth control. But now it's just not happening. It's so frustrating because this is a healthy marriage. Not abusive. And it just seems to not be working. And both our doctors have said everything seems fine! Starting to feel desperate and discouraged. Any tips will help!