Hi there,
By "wood stuff" do you mean chips? That would be worse than sand, not better. Please put them on paper towels immediately (the best choice for young and ill geckos). Also, your tank temperature is too high. Try to get a temperature gradient arranged so that the temps range from 80 degrees at the cool end of the tank, up to 90 degrees at the warm end.
Your geckos may have become impacted by the sand...did they stop defecating (pooping) as well as not eating? Were they eating the sand before (deliberately or accidentally)? Sometimes soaking them in a shallow container of warm water will help them move their bowels, or giving them a small amount of vegetable oil (dab it on their lips so they can lick it). If they still will not eat, you should consult a veterinarian. The link below may be helpful in finding a vet in your area.
Hope this helps.
Regards,
Amy
Herp vets