Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
van thanh » van tuan
dang xay » dang van, van xay
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh
ha duc » ho duc, ha dac, xa duc
ha tuc » ha thuc, va tuc, thai tuc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky dang xay hoi. hieu van ((ha tuc) OR (ha duc)) ((van thanh) OR (ban thanh)) tai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky dang xay hoi. hieu van ((ha tuc) or (ha duc)) ((van thanh) OR (ban thanh)) tai cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky dang xay hoi. hieu van ((ha tuc) or (ha duc)) ((van thanh) OR (ban thanh)) tai cua tre*.