Perhaps you should try some spelling variations:
hien hanh » dieu hanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
dung cong » dung trong
qua dung » quang dung, su dung, qua song
cong san » cong tac
san tran » tan tran, ban tran, dang tran
tran tap » toan tap, tran tan, tran tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien hanh) or (hieu manh)) - ((thanh tung) OR (thanh cong)) qua dung cong san tran tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien hanh) OR (hieu manh)) - ((thanh tung) OR (thanh cong)) qua dung cong san tran tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien hanh) or (hieu manh)) - ((thanh tung) OR (thanh cong)) qua dung cong san tran tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien hanh) or (hieu manh)) - ((thanh tung) OR (thanh cong)) qua dung cong san tran tap*.