Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van nang » van quang, van ban, van dong
va triet » va thiet, va trien, ve triet
hieu va » hieu qua
cam duc » cam xuc, cao duc, pham duc
va hanh » van hanh, va thanh, va danh
hanh de » hanh ve, hanh kem
v nang » va nang, vu nang, voi nang
de va » de van, te va, ke 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: toc sach ((v nang) OR (van nang)) xa hoi. ((hieu va) OR (lieu va)) cam duc va hanh de va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((v nang) OR (van nang)) xa hoi. ((hieu va) or (lieu va)) cam duc va hanh de va triet~".
• Adding a wildcard symbol may retrieve word variants: toc sach ((v nang) OR (van nang)) xa hoi. ((hieu va) or (lieu va)) cam duc va hanh de va triet*.