Perhaps you should try some spelling variations:
thanh trung » thanh tung
chiet tach » chieu sach
hanh trang » canh tranh, hanh trinh, minh trang
cong cong » cong dong, trong cong, dung cong
cong tac » cong ty
tac tren » rac tren, tai tren, tap tren
tren cau » tren ca, tren cay, tren tau

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((dieu hanh) or (chiet tach)) - ((hanh trang) OR (thanh trung)) cua cong cong tac tren cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((dieu hanh) OR (chiet tach)) - ((hanh trang) OR (thanh trung)) cua cong cong tac tren cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((dieu hanh) or (chiet tach)) - ((hanh trang) OR (thanh trung)) cua cong cong tac tren cau".
• Adding a wildcard symbol may retrieve word variants: theo ((dieu hanh) or (chiet tach)) - ((hanh trang) OR (thanh trung)) cua cong cong tac tren cau*.