Guys please help me on understanding Power Bi!

We do a thing where one day a week for an hour we mass call potential candidates. Someone tried explaining to me how to do this on the applicant correspondence page on power bi and I just don’t understand how they found all the applicants. Whenever I enter a search nothing comes up, or it’s all dead leads idk what I’m doing wrong. We also use recruitecare if anyone understands how the hell that even works, it’s an eyesore