Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
hieu manh » chieu xanh, hieu nganh, dieu hanh
tranh hai » tranh thai, thanh hai, tran hai
dung cong » dung trong
doc hieu » toc thieu, hoc thieu, hoc hien
hai dung » hai duong, mai dung, hai dang
dan toan » van toan, dan than, manh toan

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 manh - hanh tranh hai dung cong ((dan toan) or (anh tuan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu manh - hanh tranh hai dung cong ((dan toan) OR (anh tuan)) cao.
• Adding a wildcard symbol may retrieve word variants: doc hieu manh - hanh tranh hai dung cong ((dan toan) or (anh tuan)) cao*.