Perhaps you should try some spelling variations:
thanh trung » thanh tung
thong cong » trong cong, tong cong, thong thong
doi chieu » doc hieu, doi chi, mot chieu
thanh cac » hanh cac, thanh bac, thanh ca
ho chieu » theo chieu, hoc thieu, mot chieu
trung he » trung ha, trong he, trung hieu
cong tac » cong ty
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) OR (doi chieu)) sach - thanh trung he thong cong tac ((khan cap) or (thanh cac))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - thanh trung he thong cong tac ((khan cap) OR (thanh cac)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (doi chieu)) sach - thanh trung he thong cong tac ((khan cap) or (thanh cac))".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (doi chieu)) sach - thanh trung he thong cong tac ((khan cap) or (thanh cac))*.