Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
thien anh » thien danh, tien anh, thien thanh
tranh cua » doanh cua, manh cua
cong cong » cong dong, trong cong, dung cong
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
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 manh) or (thien anh)) - canh tranh cua cong cong bai toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (thien anh)) - canh tranh cua cong cong bai toan ban*.