Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
trinh quan » trinh luat, trinh han
hang cong » dang cong, hang nong, bang cong
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cao » toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu quang - hanh ((trinh quan) or (tinh quang)) hang cong san toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu quang - hanh ((trinh quan) OR (tinh quang)) hang cong san toan cao.
• Adding a wildcard symbol may retrieve word variants: ho hieu quang - hanh ((trinh quan) or (tinh quang)) hang cong san toan cao*.