They lacked the necessary resources.
Question: Why didn’t Comey and his 150 clowns find these 15,000 emails?
Answer: They lacked the necessary resources.
All the FBI needed to do was ask the State Dept to search its e-mail archives for Hillary’s e-mail ID and sort the results by recipient. There would be some cleanup needed, but large organizations search for e-mails all the time for lawsuits, personnel issues and the like.