Perhaps you should try some spelling variations:
trinh quan » trinh luat, trinh han
hieu lang » chieu sang, hieu quang, nhieu tang
hang cong » dang cong, hang nong, bang cong
hoi hieu » hoi phieu, hoi tieu, moi hieu
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh 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: hoi hieu lang - hanh ((trinh quan) or (tinh quang)) hang cong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - hanh ((trinh quan) OR (tinh quang)) hang cong dan toan cao.
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - hanh ((trinh quan) or (tinh quang)) hang cong dan toan cao*.