Perhaps you should try some spelling variations:
thanh trung » thanh tung
trung gap » trung cap, trung gay, trung lap
gap trong » ap trong, gay trong, lap trong
doc hieu » toc thieu, hoc thieu
cong dan » cong san, cong tan, huong dan
toan ban » van ban
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: ((doc hieu) OR (hoc hien)) sach - thanh trung gap trong cong dan ((toan ban) or (khan cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc hien)) sach - thanh trung gap trong cong dan ((toan ban) OR (khan cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) OR (hoc hien)) sach - thanh trung gap trong cong dan ((toan ban) or (khan cap))".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) OR (hoc hien)) sach - thanh trung gap trong cong dan ((toan ban) or (khan cap))*.