Obviously, there is the irony that she ignored them, slow played them, and she obstructed them by destroying 33,000 emails with Bleach Bit, and she couldn't remember anything during her testimony. But now there is something that she wants, and it must happen yesterday.
But more important is the fact that the information cannot be released and she KNOWS it. 1) parts of it are classified
2) any information released could prejudice and undermine the investigation and it is SOP NOT to release info during the investigatory phase, and 3) Loretta Lynch has thus far refused to give Comey and the FBI a search warrant to begin investigating the emails - this was revealed today in the news.
Hillary doesn't want what was in those emails made public, but she does want to play the victim.