Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
tinh va » tich va, trinh van, trinh vat
tinh vi » trinh vi, tinh voi, dinh vi
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
luc va » duc va, tuc va, loc va
va coc » va cuoc, va cac, va hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky lang xa hoi. hieu va coc luc va ((tinh vi) OR (tinh va)) ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang xa hoi. hieu va coc luc va ((tinh vi) OR (tinh va)) ((cua tre) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky lang xa hoi. hieu va coc luc va ((tinh vi) OR (tinh va)) ((cua tre) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: su sach ky lang xa hoi. hieu va coc luc va ((tinh vi) OR (tinh va)) ((cua tre) or (cua viet))*.