Perhaps you should try some spelling variations:
phan thuc » nhan thuc, phap thuc, pham thuc
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan, thuc vat
sach ly » sach y, sach lo, sach ty
ly hang » ly quang
hieu ve » hieu va, hieu van
ve phan » va phan, ke phan, ve phat
dan dan » dang dan, ban dan, dao dan
dan lap » phan lap, dan luan
lap cua » lai cua, tap cua, lam cua
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, 5 hoi

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 ly hang ((x hoi) or (x ho)). hieu ve phan thuc dan dan lap cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ly hang ((x hoi) OR (x ho)). hieu ve phan thuc dan dan lap cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ly hang ((x hoi) or (x ho)). hieu ve phan thuc dan dan lap cua tre*.