Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hanh trinh » canh tranh, hanh chinh
hien hanh » dieu hanh
dung cong » dung trong
trinh va » trinh van, trinh vat, trinh ve
dan chan » dan gian, van chat
va dung » van dung, va duong, vat dung

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 (chieu xanh)) - hanh trinh va dung cong ((dan chan) OR (dan ca)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien hanh) OR (chieu xanh)) - hanh trinh va dung cong ((dan chan) OR (dan ca)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien hanh) or (chieu xanh)) - hanh trinh va dung cong ((dan chan) OR (dan ca)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien hanh) or (chieu xanh)) - hanh trinh va dung cong ((dan chan) OR (dan ca)) cau*.