Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van dai » vanh dai, van dao, van hai
dai thu » dai thua, dai thuc, doi thu
thu ban » thu hang
tai cua » thai cua, tai cuc, hai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang xa hoi. hieu van dai thu ban thanh ((((tai cua) or (dai cua))) or (tri cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. hieu van dai thu ban thanh ((((tai cua) OR (dai cua))) OR (tri cua)) te.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. hieu van dai thu ban thanh ((((tai cua) or (dai cua))) or (tri cua)) te*.