Perhaps you should try some spelling variations:
chieu xanh » chieu sang, chieu tinh, hieu manh
chieu sach » chinh sach, chiet tach, chieu sang
hanh trinh » canh tranh, hanh chinh
trinh van » trinh han, trinh quan, trinh toan
hang cong » dang cong, bang cong, thanh cong
hang nong » thang long, han tong
ban toan » bai toan, ban than, van 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: hoc ((chieu xanh) OR (chieu sach)) - hanh trinh van ((hang cong) or (hang nong)) ban toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sach)) - hanh trinh van ((hang cong) OR (hang nong)) ban toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) OR (chieu sach)) - hanh trinh van ((hang cong) or (hang nong)) ban toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) OR (chieu sach)) - hanh trinh van ((hang cong) or (hang nong)) ban toan cau*.