Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
xa thanh » va thanh, ha thanh, ta thanh
tu sach » thu sach, su sach, te sach
nam tuc » nam thuc, nam truc, nam tu
xa hanh » xa khanh, va hanh, da hanh
cua tre » cua te, cuu tre, dua tren
y nang » ky nang, ly nang, v nang
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: tu sach y nang x hoi. hieu van nam tuc ((xa hanh) OR (xa thanh)) vai ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang x hoi. hieu van nam tuc ((xa hanh) or (xa thanh)) vai ((cua tre) OR (cua triet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x hoi. hieu van nam tuc ((xa hanh) or (xa thanh)) vai ((cua tre) OR (cua triet))*.