Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
xuc va » tuc va, luc va, xac va
vi cua » vai cua, di cua

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 y nang xa hoi. ((hieu ve) or (hieu van)) cam ((xuc va) OR (duc va)) thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. ((hieu ve) OR (hieu van)) cam ((xuc va) OR (duc va)) thanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. ((hieu ve) or (hieu van)) cam ((xuc va) OR (duc va)) thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. ((hieu ve) or (hieu van)) cam ((xuc va) OR (duc va)) thanh vi cua tre*.