Perhaps you should try some spelling variations:
dung cong » dung trong
chi xanh » chi anh, chi danh, chi hanh
tranh su » trinh su, trang su, tranh cua
cong dan » cong san, cong tan, huong dan
khan cap » khan ap, than cap, khoan cam
phan cau » phan dau, phan cac, phan tu
doi chi » doi khi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doi chi xanh - canh tranh su dung cong dan ((khan cap) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chi xanh - canh tranh su dung cong dan ((khan cap) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: doi chi xanh - canh tranh su dung cong dan ((khan cap) or (phan cau))*.