Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh cho » thanh pho, thanh cha, thanh chu
cua viet » hoa viet, cua vat, cua dieu
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
te sach » toc sach
dan ban » van ban, can ban, dan ba
hac dan » nhac dan, hoc dan, cac dan
van hac » van hoc, van ha, van hai
ca viet » va viet, co viet, hoa viet
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho

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

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