Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
thuc sach » thuoc sach, thu sach, thuc cach
trinh han » trinh quan
dong cong » duong cong, dung cong, cong cong
dang cong » dung cong
thang ban » hang ban, tang ban, thanh ban
hoc thuc » hoc huu
ban cau » bang cau, ban can, van cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thuc sach - canh trinh han ((dong cong) or (dang cong)) thang ban cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thuc sach - canh trinh han ((dong cong) OR (dang cong)) thang ban cau*.