Perhaps you should try some spelling variations:
tang nguoi » thang nguoi, tang nguon, nang nguoi
dang nguoi » dung nguoi, nang nguoi, thang nguoi
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh cac » trinh cac, thanh cac, tranh cai
doc hieu » toc thieu, hoc thieu, hoc hien
dan toan » van toan, dan than, manh 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: doc hieu xanh - canh tranh cac ((dang nguoi) or (tang nguoi)) dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - canh tranh cac ((dang nguoi) OR (tang nguoi)) dan toan cau.
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh tranh cac ((dang nguoi) or (tang nguoi)) dan toan cau*.