Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
cac duc » cac du, cao duc, cac dac
sach ky » sac ky, sach y, sach ty
va tinh » may tinh
cua tre » cua te, cuu tre, dua tren
te sach » toc sach
x hoi » xa hoi, o hoi, x ho

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: te sach ky nang x hoi. hieu van cac duc ((ban thanh) OR (va tinh)) dat ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang x hoi. hieu van cac duc ((ban thanh) or (va tinh)) dat ((cua tre) OR (cua triet))~".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang x hoi. hieu van cac duc ((ban thanh) or (va tinh)) dat ((cua tre) OR (cua triet))*.