According to Pete Williams of NBC News who was on tv yesterday, there were 650k emails on Weiner's computer. The FBI was only interested in the ones to/from Huma. Of those, they were only interested in those related to Hillary. Of those, they ran a program to compare them to original emails for duplicates. Of that subset, most were found to be duplicates of what the FBI already had. So there weren't that many that were new that fit their criteria. They were reviewed, and none were found that would change the FBI's original conclusion.