Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
chieu tinh » trieu tinh, lieu tinh, chau tinh
tranh cua » manh cua
doanh cua » doanh luan
ban cong » bang cong, van cong, phan cong
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu quang) or (chieu tinh)) - hanh ((tranh cua) OR (doanh cua)) ban cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu quang) OR (chieu tinh)) - hanh ((tranh cua) OR (doanh cua)) ban cong san toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu quang) or (chieu tinh)) - hanh ((tranh cua) OR (doanh cua)) ban cong san toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu quang) or (chieu tinh)) - hanh ((tranh cua) OR (doanh cua)) ban cong san toan ban*.