Most of the victims were teenagers and nine bodies haven't been recovered yet.
The ship was raised and transported to a port in March. Workers haves since found four pieces of suspected human bones.
The Oceans Ministry says its search team found "many" more such bone fragments today but didn't say how many. It says DNA tests are needed to confirm whether the remains belong to any of the missing victims.
The government in March said it had found bones believed to be from missing victims before correcting they belong to animals.