If you are on stage one, it might be too early to introduce yoghurt. I also found that yoghurt made me even more hungry. Try hard boiled eggs, pop one every time you feel hungry. I ate around 8 eggs per day on stage one. Pumpkin seeds helped me as well (didn’t do any other seeds on stage one, but these did not bother me) and if you get the ones in shells they keep you busy so you don’t eat that many of them 🙂
Home made kefir with whole milk would be a better alternative to yoghurt. I suggest you try that. You would get protein, some fat and probiotic benefits out of it. Search the forum, there are tons of posts about it. If fermented right, there is no lactose left in the kefir so it is better than yoghurt (especially commercially made yoghurt where you don’t know how it has been fermented).
Best of luck to you!