Not all hens are exposed to a roo. Are these free range eggs? You have a better chance if they are. Where they marked fertile? There was a health food place near here that had some fertile eggs last spring. I was tempted to try them in a hatch! Good luck!
P.S. Give us some more details on the eggs you bought please. LOL
P.S. Give us some more details on the eggs you bought please. LOL