Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thuc ban » thuoc ban, thuc dan, thu ban
thanh vi » hanh vi, thanh va, thanh ve
cua viet » ca viet, hoa viet, cua vat
su sach » vu sach
so sach » so sanh, bo sach, co sach
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
van am » van nam, van lam, van dam
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: ((su sach) or (so sach)) ky tang xa hoi. hieu van am thuc ban thanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky tang xa hoi. hieu van am thuc ban thanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky tang xa hoi. hieu van am thuc ban thanh vi cua viet*.