I concur with Roy. Live fish in a shallow dish with water ( so they'll splash a bit ) or earthworm of the appropriate size ( no red one's ), those are the best to get them started. If they've eaten once, you can try scenting with what they ate on other food items like pinkies.

Watch them if they eat, it can become quite a fight for the same food. And they'll also eat faster when they're in a group. If they see another snake eating, they'll try it themselves....

You've probably done that, but seperate the young ones from the adults.