Perhaps you should try some spelling variations:
thien van » thi van
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
thu sach » tu sach, thuat sach, thuoc sach
nam duoc » nam thuoc, da duoc, dat duoc
hieu van » hieu va, lieu va, hieu ve
tai cua » thai cua, tai cuc, tri cua
lam duc » lam duoc, pham duc, lam dung
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y nang xa hoi. ((hieu van) or (thien van)) ((lam duc) OR (nam duoc)) ban thanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang xa hoi. ((hieu van) OR (thien van)) ((lam duc) OR (nam duoc)) ban thanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang xa hoi. ((hieu van) or (thien van)) ((lam duc) OR (nam duoc)) ban thanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang xa hoi. ((hieu van) or (thien van)) ((lam duc) OR (nam duoc)) ban thanh tai cua tre*.