Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
vat dung » van dung, viet dung, mat duong
sai cua » dai cua, hai cua, lai cua
va dung » van dung, va duong, va ung
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
hieu he » hieu ve, hiem he, hieu le
he nam » ha nam, nghe nam

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