Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
duc ban » duc tan, duc van, dua ban
cam duc » cam xuc, cao duc, pham duc
van cam » van nam, van lam, van cau
tu sach » thu sach, te sach, tu cach
ly nang » ky nang, ly hang, ly vang
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
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) OR (su sach)) ((ly nang) or (ty xang)) xa hoi. hieu van cam duc ban thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ((ly nang) OR (ty xang)) xa hoi. hieu van cam duc ban thanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) ((ly nang) or (ty xang)) xa hoi. hieu van cam duc ban thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) ((ly nang) or (ty xang)) xa hoi. hieu van cam duc ban thanh vi cua tre*.