Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
tong cong » trong cong, cong cong, dang cong
dung cong » dung trong
dan toan » van toan, dan than, manh toan
toan tap » toan ban

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo hieu lang - hanh trinh cua ((tong cong) or (dung cong)) dan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - hanh trinh cua ((tong cong) OR (dung cong)) dan toan tap*.