Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
thanh tung » thanh cong
hieu cach » hieu cac, chieu sach, hieu ca
cua dang » cua cong
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.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thien hach) or (hieu cach)) - thanh tung ((cua dang) or (cua ban)) cong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien hach) OR (hieu cach)) - thanh tung ((cua dang) OR (cua ban)) cong tan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thien hach) or (hieu cach)) - thanh tung ((cua dang) or (cua ban)) cong tan toan cau*.