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 ve » trinh he, trinh va, trinh vi
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap
ve dang » le dang, vu dang, de dang

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 ve dang cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sang)) - hanh trinh ve dang cong san toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) or (chieu sang)) - hanh trinh ve dang cong san toan cau*.