Perhaps you should try some spelling variations:
thanh trung » thanh tung
hoc thieu » toc thieu, hoc hien
trung vap » trung cap, trung va, trung van
vap nhung » va nhung, ve nhung, voi nhung
ho chieu » theo chieu, doi chieu, mot chieu
cong tan » cong tac, cong san, cong thanh
toan tap » toan ban

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 (hoc thieu)) sach - thanh trung vap nhung ((cong tan) or (huong dan)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) sach - thanh trung vap nhung ((cong tan) OR (huong dan)) toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (hoc thieu)) sach - thanh trung vap nhung ((cong tan) or (huong dan)) toan tap".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (hoc thieu)) sach - thanh trung vap nhung ((cong tan) or (huong dan)) toan tap*.