Perhaps you should try some spelling variations:
hoc thieu » hoc hien
hanh sinh » hanh tinh, hanh dinh, hinh sinh
dong cong » duong cong, dung cong, dang cong
sinh van » sinh vat, dinh van, sinh va
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cap » khan cap, thanh lap, thanh cac

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

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