Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach ty » sach tu, sach thu, xach tay
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
sai ky » sac ky
va cau » van cau, va cac, va dau
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((((sach ty) OR (sach y))) or (sai ky)) nang x hoi. hieu va cau truc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((((sach ty) OR (sach y))) OR (sai ky)) nang x hoi. hieu va cau truc va hanh vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((((sach ty) OR (sach y))) or (sai ky)) nang x hoi. hieu va cau truc va hanh vi cua viet".
• Adding a wildcard symbol may retrieve word variants: tu ((((sach ty) OR (sach y))) or (sai ky)) nang x hoi. hieu va cau truc va hanh vi cua viet*.