Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
hanh tranh » canh tranh, hanh trinh, hanh trang
tranh cua » doanh cua, manh cua
tong cong » trong cong, cong cong, dung cong
cua tong » cua cong, cua dong, cua nong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai 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: hoc ((((dieu hanh) or (hien hanh))) or (hieu nganh)) - hanh tranh cua tong cong tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((((dieu hanh) OR (hien hanh))) OR (hieu nganh)) - hanh tranh cua tong cong tap toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((((dieu hanh) or (hien hanh))) or (hieu nganh)) - hanh tranh cua tong cong tap toan cao*.