Paying off negative accounts does not make them positive. It simply makes them current negative accounts.
What you've done buy paying these accounts off is made them look like they just happened which hurts your scores tremendously.
Make sure you always ask for a deletion or a change of status to "pays as agreed" from the creditor
BEFORE you pay off any derogatory accounts next time!
Sample Pay For Delete Letters
You can still try to get them deleted and/or updated, but it won't be as easy. Dispute them with the credit bureaus.