Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
ky trong » ly trong, ke trong, cay trong
nam thuc » nam thuoc, am thuc, nam thu
su sach » so sach, vu sach
ky tang » ky nang, ky dang, kho tang
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va hang » van hang, va nang, va lang
hang di » hang doi, hang vi, hang dien
cua tre » cua te, cuu tre, cua triet
ve nam » he nam, va nam, le nam
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuoc sach) or (su sach)) ((ky trong) or (ky tang)) xa hoi. hieu ve nam thuc va hang di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (su sach)) ((ky trong) OR (ky tang)) xa hoi. hieu ve nam thuc va hang di cua tre.
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) or (su sach)) ((ky trong) or (ky tang)) xa hoi. hieu ve nam thuc va hang di cua tre*.