Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
chong phap » phuong phap
phap toan » phap hoan, phap luan, phap phan
chi xanh » chi anh, chi danh, chi hanh
cua dang » cua cong
toan cau » toan cao, toan ban, toan tap
doi chi » doi khi

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: doi chi xanh - thanh tuong ((cua dang) OR (cua ban)) chong phap toan cau~.
• Adding a wildcard symbol may retrieve word variants: doi chi xanh - thanh tuong ((cua dang) or (cua ban)) chong phap toan cau*.