ถ้ายังงั้น ☊ thaaF yangM nganH 
in that case, if that's how it is like: If that → →
if so, if that is the case ☊ 
nếu thế ☊ If that's all the thanks I get, I won't bother in future! ☊ bother ☊
If that is the case (= if the situation described is true), we need more staff. ☊ case ☊
I'd rather email than phone, if that's OK by you. ☊ than ☊