Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
te sach » toc sach
van dau » van dao, phan dau
dau xuc » dau xac, dau xua, dau nuoc
va hanh » van hanh, va thanh, va danh
cua tre » cuu tre, cua triet, dua tren
y nang » ky nang, ly nang, v nang
xuc va » duc va, tuc va, luc va
cua te » cua tu
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y nang ((x hoi) or (xa hoi)). hieu van dau xuc va hanh vi ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((x hoi) OR (xa hoi)). hieu van dau xuc va hanh vi ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ((x hoi) or (xa hoi)). hieu van dau xuc va hanh vi ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((x hoi) or (xa hoi)). hieu van dau xuc va hanh vi ((cua tre) OR (cua te))*.