Noymira,
Around here broodies just happen, but it helps to have a silky hen as they are really good at it. I've never "encuraged a broody" but let me know how it goes for you? Once they are broody I just put the eggs I want under them and let the hens do the rest of the work hatching and raising the young..... so easy! I bet any day now your hens will start to go broody, pick them up tonight and see if anyone is missing their breast underfeathers. If they are, it's called a brood patch and they are about to go broody. Good luck!