Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
trinh cua » tinh cua, trinh luat, trinh quan
dung cong » dung trong
doc hieu » toc thieu, hoc thieu
cua dung » cua dang, cua dong, qua dung
cong dan » cong san, cong tan, huong dan
than cap » khan cap, thanh lap, thanh cac
phan cau » phan dau, phan cac, phan tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doc hieu) OR (hoc hien)) xanh - canh trinh cua dung cong dan ((than cap) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc hien)) xanh - canh trinh cua dung cong dan ((than cap) OR (phan cau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) OR (hoc hien)) xanh - canh trinh cua dung cong dan ((than cap) or (phan cau))".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) OR (hoc hien)) xanh - canh trinh cua dung cong dan ((than cap) or (phan cau))*.