Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
nam thuc » nam thuoc, am thuc, nam thu
tay tang » tay lang, tay trung, tay quang
so sanh » do sanh
danh de » hanh de, dan de, dang de
va danh » va dinh, va dan, va hanh
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
de cua » le cua, te cua, dieu cua
cua te » cua tu
ve nam » he nam, va nam, le nam
ha hoi » hoa hoi, xa hoi, va hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (so sanh)) tay tang ((ha hoi) or (ha noi)). hieu ve nam thuc va danh de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (so sanh)) tay tang ((ha hoi) OR (ha noi)). hieu ve nam thuc va danh de cua te.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (so sanh)) tay tang ((ha hoi) or (ha noi)). hieu ve nam thuc va danh de cua te*.