Perhaps you should try some spelling variations:
thanh trong » thanh trung, tranh trong, hanh trong
theo chieu » theo tieu, ho chieu, theo chu
mot chieu » doi chieu, ho chieu
dung cong » dung trong
cac dung » cach dung, cac duong, tac dung
cong dan » cong san, cong tan, huong dan
khan cap » khan ap, than cap, khoan cam
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: ((theo chieu) or (mot chieu)) sach - thanh trong cac dung cong dan ((khan cap) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (mot chieu)) sach - thanh trong cac dung cong dan ((khan cap) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) or (mot chieu)) sach - thanh trong cac dung cong dan ((khan cap) or (phan cau))*.