Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, mang xa, ang xa
nam tuc » nam truc, nam tu, nam thuoc
xa hanh » xa thanh, xa khanh, va hanh
cua tre » cua te, cuu tre, dua tren

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ty xang xa hoi. hieu van ((nam tuc) or (nam thuc)) xa hanh vai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty xang xa hoi. hieu van ((nam tuc) OR (nam thuc)) xa hanh vai ((cua tre) OR (cua triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty xang xa hoi. hieu van ((nam tuc) or (nam thuc)) xa hanh vai ((cua tre) OR (cua triet))*".