Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hanh tranh » canh tranh, hanh trinh, hanh trang
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh cua » doanh cua, manh cua
bang cong » dang cong, bang song, hang cong
doc hieu » toc thieu, hoc thieu, hoc hien
dan chan » dan gian, dan ca, van chat
chan cau » phan cau, can cau, chinh cau

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: doc hieu xanh - hanh tranh cua ((nhung cong) OR (bang cong)) dan chan cau~.
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - hanh tranh cua ((nhung cong) or (bang cong)) dan chan cau*.