Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
doi chieu » doc hieu, doi chi, ho chieu
tranh cua » doanh cua, manh cua
trong ban » trong san, trong tan, trong quan
cua dung » cua dang, cua dong, qua dung
ban toan » bai toan, ban than, van toan
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: ((doi chieu) or (hoc hien)) xanh - hanh tranh cua dung trong ban toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (hoc hien)) xanh - hanh tranh cua dung trong ban toan cao.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (hoc hien)) xanh - hanh tranh cua dung trong ban toan cao*.