Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
tong cong » trong cong, cong cong, dung cong
thanh dau » thanh dat, thanh mau, thanh dan
thanh dam » thanh dat, thanh nam, thanh tam
ho chieu » theo chieu, hoc thieu, doi chieu
doc hieu » toc thieu, hoc thieu, hoc hien
trinh va » trinh van, trinh vat, trinh ve
cong van » cong vang, cong san, song van
va tong » va thong, va tuong, va trong

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: ((ho chieu) OR (doc hieu)) xanh - canh trinh va tong cong van ((thanh dau) OR (thanh dam))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (doc hieu)) xanh - canh trinh va tong cong van ((thanh dau) OR (thanh dam))~".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doc hieu)) xanh - canh trinh va tong cong van ((thanh dau) OR (thanh dam))*.