Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
kho tang » cao tang
hang doi » hang di, hang loi, huong doi
ban hang » ngan hang
hieu van » hieu va, thien van, lieu va
cam cuu » cham cuu, cap cuu
doi cua » dai cua, hoi cua
cuu ban » cuu van, cua ban, cuu san
van cam » van nam, van lam, van cau
cua tre » cua te, cuu tre, cua triet

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)) ((kho tang) or (ky nang)) xa hoi. hieu van cam cuu ban hang doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ((kho tang) OR (ky nang)) xa hoi. hieu van cam cuu ban hang doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ((kho tang) or (ky nang)) xa hoi. hieu van cam cuu ban hang doi cua tre*.