I don't know why the vertices has changed. Although when I went out to look at the original edit mode. There was nothing wrong. This happens only in the right hand. Previously, I had weighted in the hip section. But when I check the weight of the hips, it has no effect on the hand. (pic 2) Please guide me how I can solve this problem. Thank you.
Then you set weight for a vertex, let say 100%, for 1 bone it doesn't mean that this vertex will move 100% with this bone. Not at all. One vertex may be in several groups at the same time, and the sum of all these weights may be more than 1. So the influence that bone has at the specific point equals its weight divided by the sum of all weights.
If you select a point, you may see something like this:
From this, you may find that other bones affects on this point.
And of-course, you may find useful to use auto-normalize option:
Which keeps the sum of weights always equal to 1.