Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
tranh cua » doanh cua, manh cua
dong cong » duong cong, dang cong, cong cong
dung cong » dung trong
ho chieu » theo chieu, hoc thieu, doi chieu
tac toan » tap toan, tam toan, hach toan
toan cao » toan ban, toan tap
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (doi chi)) xanh - hanh tranh cua ((dong cong) OR (dung cong)) tac toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chi)) xanh - hanh tranh cua ((dong cong) OR (dung cong)) tac toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (doi chi)) xanh - hanh tranh cua ((dong cong) OR (dung cong)) tac toan cao*".