Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cua viet » ca viet, hoa viet, cua vat
cao hoi » cau hoi, cao hoc, tao hoi
van hac » van hoc, van hai, van chat
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
co hoi » co hoc, co loi
van ha » van hoa, van chat, van hanh
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach y nang ((cao hoi) or (co hoi)). thien ((van hac) OR (van ha)) duc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach y nang ((cao hoi) OR (co hoi)). thien ((van hac) OR (van ha)) duc va hanh vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach y nang ((cao hoi) or (co hoi)). thien ((van hac) OR (van ha)) duc va hanh vi cua viet".
• Adding a wildcard symbol may retrieve word variants: thuat sach y nang ((cao hoi) or (co hoi)). thien ((van hac) OR (van ha)) duc va hanh vi cua viet*.