Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
nhung cong » dung cong, thong cong, hang cong
hoc thien » hoc hien, hoc thieu, hoc thiet
trung cap » truong cao, trung tam
tang luan » dung luan
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh ((trung cap) OR (tang luan)) nhung cong tan toan cau~.
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh ((trung cap) or (tang luan)) nhung cong tan toan cau*.