"Anh ấy bỗng trở về."
Translation:He suddenly returns.
Yes, "trở về", "quay lại" and "trả lại" are the same word in English (return). But:
"Trở về" is used to indicate someone returns home, or where they belong to (such as their home, where they were born.)
"Quay lại" is used to indicate someone comes back after leaving a place (the same place).
And "trả lại" is used to indicate returning back something in the right place, or returning back something that you borrowed.