請問：H1B如何在美辦理H1B Visa (要回國一段時間)

I know the title is very confusing, let me try to make it clear:
1. I was using OPT before I changed to H1B status
2. Later I came back China temproraliy for visiting my parents and I applied H1B visa again.
3. NOW I might be assigned of staying in China for a few weeks due to my job. My friend told me that 因為我已經在國內申請過H1B,這次就不需要回國簽證了，隻需要把材料寄到NewYork,就可以在這裏拿到H1B

請問，is it true? and If yes, how does it work?

I do appreciate for any help!