Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
cang thang » cong thanh, dang thanh
tranh cua » doanh cua, manh cua
dang cang » dang cong, dang bang, dang dang
thang ban » hang ban, tang ban, thanh ban
cua dang » cua cong, cua ban
hieu ca » hieu cac, hieu cua, hieu va
ban can » ban dan, ban hang, ban hanh

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: hoc ((thieu sach) OR (hieu ca)) - canh tranh cua dang cang thang ban can~.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (hieu ca)) - canh tranh cua dang cang thang ban can*.