Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hanh tranh » canh tranh, hanh trinh, hanh trang
hoc chieu » hoc thieu, ho chieu, hoc hien
cua thong » cua thuong, cua khong, suat thong
cua tong » cua cong, cua dong, cua nong
cong dot » cong mot, cong dong, cong doan
cong do » cuong do, cong so, cong co

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 - hanh tranh ((cua thong) OR (cua tong)) ((cong do) or (cong dot)) van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chieu xanh - hanh tranh ((cua thong) OR (cua tong)) ((cong do) OR (cong dot)) van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu xanh - hanh tranh ((cua thong) OR (cua tong)) ((cong do) or (cong dot)) van ban".
• Adding a wildcard symbol may retrieve word variants: hoc chieu xanh - hanh tranh ((cua thong) OR (cua tong)) ((cong do) or (cong dot)) van ban*.