Perhaps you should try some spelling variations:
sach danh » sach tranh, sach dao, sach dung
xac danh » xac dinh, tac danh, cac doanh
cua viet » hoa viet, cua vat, cua dieu
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
hieu he » hieu ve, hiem he, hieu le
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
ca viet » va viet, co viet, hoa viet
he nam » ha nam, nghe nam
ma hoi » mai hoi, xa hoi, ma hoa

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 ky tang ma hoi. hieu he nam thu ((xac danh) OR (sach danh)) sai ((cua viet) or (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang ma hoi. hieu he nam thu ((xac danh) OR (sach danh)) sai ((cua viet) OR (ca viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky tang ma hoi. hieu he nam thu ((xac danh) OR (sach danh)) sai ((cua viet) or (ca viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang ma hoi. hieu he nam thu ((xac danh) OR (sach danh)) sai ((cua viet) or (ca viet))*.