I'm not bonding with my adopted baby?

I adopted a baby 2 weeks ago and am having a hard time attaching to him as well as it seems like he has a hard time attaching to me. He is 1 y.o. He is not responding to cuddles, playing, reading books and pointing on objects. He has a blank stare or crawls away from me. He also eats so much (like 20 bottles of formula a day plus solids) and will scream very loud until I feed him to the point he is so full that he is spitting food and can't eat any more. Couple of hours later this repeats. I also adopted a little girl at the same time and we love each other, play a lot, snuggle and have a fantastic bond together. I wonder what I can do to attach to this baby. I'm having a very hard time loving him. I also have 2 other biological children whom I love very much.