Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
nang doc » nang luc
ban hang » ngan hang
nam thuc » nam thuoc, am thuc, nam thu
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
doc hoc » duoc hoc, toc hoc, duc hoc
va nam » van nam, ha nam, va nay

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 (toc sach)) ky nang doc hoc. lieu va nam thuc ((ban hanh) or (ban hang)) doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang doc hoc. lieu va nam thuc ((ban hanh) OR (ban hang)) doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang doc hoc. lieu va nam thuc ((ban hanh) or (ban hang)) doi cua tre*.