Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trinh, hanh trang
hien xanh » hien hanh, hien nhanh, chieu xanh
tranh qua » tranh cua, thanh qua, trinh qua
cong cong » cong dong, trong cong, dung cong
qua cong » cua cong, qua song, va cong
dan than » dan chan, ban than, van than

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: hoc hien xanh - hanh tranh qua cong cong ((((xuan toan) OR (dan than))) OR (tinh toan)) cau~.
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh tranh qua cong cong ((((xuan toan) or (dan than))) or (tinh toan)) cau*.