Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, nhung don
tranh cua » doanh cua, manh cua
hang cong » dang cong, hang nong, bang cong
ho chieu » theo chieu, hoc thieu, doi chieu
thi hieu » thi chieu, thi hien, thi dieu
tac toan » tap toan, tam toan, hach toan
toan cao » toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (thi hieu)) tinh - canh tranh cua ((nhung cong) OR (hang cong)) tac toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (thi hieu)) tinh - canh tranh cua ((nhung cong) OR (hang cong)) tac toan cao~".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (thi hieu)) tinh - canh tranh cua ((nhung cong) OR (hang cong)) tac toan cao*.