How to get fish to eat mollies?

my fish are somewhat small sized especially my fh(flower horn) i just got an tiger oscar and 10 feeder mollies and my oscar does eat but only fish flakes other then that he chases the mollies not attempting to eat it. my fh tries to eat them. how do i get them to eat it? the mollies is maybe the right size for the oscar but 1-2 bites for the fh. please help i only feed fish flakes but they eat them. should i starve them?