I had 3 Pekingese dogs - I just brought home a puppy 10 days ago Only one dog is accepting of her . The other two run - and snap at her I don't know what to do - it's not getting any better
It's still early days, make sure the other two has room to escape pup, allow them to make the moves, it will get easier I am sure.
Give it time. When I brought Georgina, my Pei puppy home my 5 year old Tibetan Spaniel, Chloe, didn't want anything to do with her. She'd growl if Georgina came anywhere near her, except when puppy was asleep, when she'd try to hump her. This went on for a good two weeks until one afternoon Chloe play bowed in front of the pup and after that I had no more problems!
If you have pen/crate then put pup in it this will allow the other dogs to get close to sniff pup without hurting the pup
In addition the crate/pen idea, I agree with Jackie - make sure the older two have 'safe places' to escape to. When my youngster came home, my oldest two's safe haven was my bedroom where pup was absolutely not allowed. He also got regular time-outs with a baby gate across the door so my older two could have some 'alone' time and do their own thing without the pup pushing his way in. For most older dogs they soon learn to adjust, but it's not always an immediate like and can take months for any real positive interactions.