Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
vat dung » va dung, viet dung, mat duong
van dung » van dong, xay dung, tin dung
hieu he » hieu ve, hiem he, hieu le
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, nang ma, sang tao
ky sang » ky nang, ky dang, ky tang
tu sach » thu sach, su sach, te sach
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 sang ma hoi. hieu he nam thu ((van dung) or (vat dung)) sai ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ma hoi. hieu he nam thu ((van dung) OR (vat dung)) sai ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang ma hoi. hieu he nam thu ((van dung) or (vat dung)) sai ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ma hoi. hieu he nam thu ((van dung) or (vat dung)) sai ((cua triet) OR (va triet))*.