Lenders use the middle of 3 scores that they obtain from Transunion, Equifax & Experian. There are some lenders who will consider doing an FHA loan as low as 580, but just because you are over that score doesn't guarantee an approval.
Improving your scores can take time, but some lenders assist with this. Ask around for lenders who offer FHA at 580 or assist with credit repair or both.
Some credit repair steps to consider until then. Keep your credit balances low, 1/3 or less of your limit will pull your scores up. Pay everyone on time or early. Don't close any accounts or pay off any old collections as they will drop your scores. Dispute any errors with each agency reporting them.
Best of luck.