Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh chua » trinh chuan, trinh cua, trinh chu
hieu lang » chieu sang, hieu quang, nhieu tang
chua bang » chu bang, chua nang, chua xang
bang song » nang song
doi hieu » doi chieu, doc hieu, doi hien
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: doi hieu lang - hanh trinh chua bang song ((dan toan) or (anh tuan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - hanh trinh chua bang song ((dan toan) OR (anh tuan)) cau.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - hanh trinh chua bang song ((dan toan) or (anh tuan)) cau*.