Perhaps you should try some spelling variations:
ban thanh » ban hanh
ban hang » ngan hang
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
lam duc » lam duoc, pham duc, nam duoc
van lam » van nam
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cua tre » cua te, cuu tre, cua triet
ve cua » le cua, de cua, te 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 ((ty nang) or (ty hang)) xa hoi. hieu van lam duc ((ban thanh) OR (ban hang)) ve cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty hang)) xa hoi. hieu van lam duc ((ban thanh) OR (ban hang)) ve cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) or (ty hang)) xa hoi. hieu van lam duc ((ban thanh) OR (ban hang)) ve cua tre*".