Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
hanh vai » hanh vi, hanh va, hanh tai
so sach » so sanh, bo sach, co sach
cao hoi » cau hoi, cao hoc, tao hoi
ve pham » v pham, ve phan, ve phat
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
co hoi » co hoc, co loi
huu va » cuu va, tuu va
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thu nang ((cao hoi) or (co hoi)). hieu ((ve pham) OR (vi pham)) huu va hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thu nang ((cao hoi) OR (co hoi)). hieu ((ve pham) OR (vi pham)) huu va hanh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach thu nang ((cao hoi) or (co hoi)). hieu ((ve pham) OR (vi pham)) huu va hanh vai cua te".
• Adding a wildcard symbol may retrieve word variants: so sach thu nang ((cao hoi) or (co hoi)). hieu ((ve pham) OR (vi pham)) huu va hanh vai cua te*.