Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh dai » hanh tai, hanh dao, vanh dai
sach ky » sac ky, sach y, sach ty
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
va cau » van cau, va cac, va dau
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
xuc va » duc va, xac va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang xa hoi. hieu va cau ((((xuc va) OR (luc va))) OR (tuc va)) hanh dai cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky lang xa hoi. hieu va cau ((((xuc va) OR (luc va))) or (tuc va)) hanh dai cua triet~".
• Adding a wildcard symbol may retrieve word variants: su sach ky lang xa hoi. hieu va cau ((((xuc va) OR (luc va))) or (tuc va)) hanh dai cua triet*.