1) come across-find something by accident .
I came across him in this concert , while I was was waiting for my wife.
2)come after-pursue ,follow.
I decided to come after my fathers footsteps in medicine.
3)come apart-break, separate.
Our friendship came apart because of this unexpected accident.
4)come around-change ones mind
I do not think that we must exert so much pressure on him he needs time to think about it and come around.
5)come along-accompany
Maybe yo have heard an iconic song "Come along with me " from Adventure time.
6)come away-become separated from something away , go away
Come away from me . I do not want to see you anymore in my flat.