The pair have both undergone surgery, with O'Hara receiving treatment on a groin injury and Craddock going under the knife due to a hamstring problem.
Craddock has been absent since December while O'Hara has been struggling for fitness of late, and news of their extended absence is yet further frustration for boss Terry Connor, whose side are bottom of the Premier League.
"Both Jamie and Jody have undergone successful operations," head of Wolves' medical department Steve Kemp told the club's official website.
"Jamie has been struggling with a groin problem for several months and every attempt had been made to maintain his availability whilst trying to strengthen and rehabilitate the groin at the same time.
"Unfortunately this was not possible and it is hoped that surgery should rectify the problem although means he will be out for a further six to eight weeks.
"Jody has also undergone a minor procedure on a persistent hamstring problem and, while it is always difficult to predict, he is hoping to be available again within five weeks if his rehabilitation progresses well."