Keep trying and you may find what your chickens like. Some of my chickens are deathly scared of anything new I give to them (my EE's) but my leghorns and Delaware will eat almost anything I put in front of them (especially yogurt!). Put the food in their familiar food bowl, and then leave them alone with it to mull things over. When you come back you may find that they have at least gotten interested or courageous enough to try it. I got mine to eat yogurt by mixing it in with their feed. Mine were wary of grape leaves until I kept insisting that they try it; now they fight like beasts over the leaves.