Perhaps you should try some spelling variations:
hoc khien » hoc hien, hoc nghien, hoc thieu
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
cong cong » cong dong, trong cong, dung cong
tinh thu » tinh thua, tinh thue, tinh thuc
cong tan » cong tac, cong san, cong thanh
tan khan » tan khang, tan nhan, toan khoan
khan cap » khan ap, than cap, khoan cam

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc khien) or (toc thieu)) tinh - hanh tinh thu cong cong tan khan cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc khien) OR (toc thieu)) tinh - hanh tinh thu cong cong tan khan cap*.