Firstly, water. I remembered I made overnight oats for myself almost everyday with a little yoghurt in it with milk. And I ate quite abit of kimchi (probiotics in them) with rice dishes such as oily meats cuts and oily fishes to help because I hated prunes. No constipation problem for me.
Try Yakult. Eat lotsa veggies like broccoli, spinach etc Take care!