Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu tinh, hieu manh
chieu sang » chieu sach, hieu lang, nhieu tang
hanh trinh » canh tranh, hanh chinh
dang cong » dung cong
trinh de » trinh den, trinh do, trinh he
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh
de dang » da dang, le dang, de tang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu xanh) or (chieu sang)) - hanh trinh de dang cong ((dan toan) OR (van toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sang)) - hanh trinh de dang cong ((dan toan) OR (van toan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) or (chieu sang)) - hanh trinh de dang cong ((dan toan) OR (van toan)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) or (chieu sang)) - hanh trinh de dang cong ((dan toan) OR (van toan)) cau*.