need help with some k-pop groups

[Raiu-Ayu]

Right now I'm kinda loving the K-Pop boy bands and I'm looking to find some more other than the ones I know.

So, I need help identifying the artists in this video


Specifically I'm looking for:
the group that appears several times from 0:20 - 0:34
the group at 0:38 - 0:43
the group that appears for a split second at 1:16 (in the blue room with the pinkish/brownish trousers)

If anyone can answer that for me I'll be so happy