Perhaps you should try some spelling variations:
lang van » dang van, tang van, hoang van
cac thuc » cach thuc, cac thu, can thuc
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
van hoc » van hoa
hieu va » lieu va, hieu qua
danh di » danh du, danh dien, danh gia
xanh di » vanh dai, xanh tai

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 lang van hoc. hieu va cac thuc vat ((danh di) or (xanh di)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang van hoc. hieu va cac thuc vat ((danh di) OR (xanh di)) su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang van hoc. hieu va cac thuc vat ((danh di) or (xanh di)) su triet*.