Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
vanh tai » hanh tai, anh tai, vanh dai
su sach » so sach, vu sach
nang co » nang cao, nang doc, nang noi
qua cac » cua cac
van tai » von tai, van tuan
y nang » ky nang, ly nang, v nang
co hoi » co hoc, co loi
ac va » tac va, bac va, mac 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 y nang co hoi. hieu qua cac ((ac va) OR (duc va)) ((vanh tai) OR (van tai)) cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang co hoi. hieu qua cac ((ac va) or (duc va)) ((vanh tai) OR (van tai)) cua triet~".
• Adding a wildcard symbol may retrieve word variants: su sach y nang co hoi. hieu qua cac ((ac va) or (duc va)) ((vanh tai) OR (van tai)) cua triet*.