Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu lang » chieu sang, hieu quang, nhieu tang
tranh qua » tranh cua, thanh qua, trinh qua
dan toan » van toan, dan than, manh 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: doc ((chieu xanh) or (hieu lang)) - hanh tranh qua ((dung cong) OR (dung trong)) dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((chieu xanh) OR (hieu lang)) - hanh tranh qua ((dung cong) OR (dung trong)) dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((chieu xanh) or (hieu lang)) - hanh tranh qua ((dung cong) OR (dung trong)) dan toan cau".
• Adding a wildcard symbol may retrieve word variants: doc ((chieu xanh) or (hieu lang)) - hanh tranh qua ((dung cong) OR (dung trong)) dan toan cau*.