Formal:
* C'est ce que vous recherchez. (This is what you are looking for.)
* Voici ce que vous recherchez. (Here is what you are looking for.)
Informal:
* C'est ça que tu cherches. (This is what you're looking for.)
* Voilà ce que tu cherches. (Here's what you're looking for.)
* C'est exactement ce que tu cherches. (This is exactly what you're looking for.)
More specific:
* C'est ce que vous cherchez, n'est-ce pas? (This is what you are looking for, isn't it?)
The best choice will depend on your audience and the specific situation.