Perhaps you should try some spelling variations:
hien hanh » dieu hanh
hang cong » hang nong, bang cong, thanh cong
dang cong » dung cong
tien anh » tieng anh, tien manh, dien anh
tranh va » tranh van, trang va, trinh va
san chan » san chang, dan chan, san chay
chan cau » phan cau, can cau, chinh cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((tien anh) or (hien hanh)) - canh tranh va ((hang cong) OR (dang cong)) san chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((tien anh) OR (hien hanh)) - canh tranh va ((hang cong) OR (dang cong)) san chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((tien anh) or (hien hanh)) - canh tranh va ((hang cong) OR (dang cong)) san chan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((tien anh) or (hien hanh)) - canh tranh va ((hang cong) OR (dang cong)) san chan cau*.