Perhaps you should try some spelling variations:
day thanh » dao thanh, dat thanh, da thanh
cham thuc » nham thuc, pham thuc, tham thuc
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
thuc day » thuc dan, thuc vat
thanh vi » hanh vi, thanh va, thanh ve
sach ly » sach y, sach ty, sach hay
sach lo » sach dao, sach doi, sach hoi
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ly) OR (sach lo)) nang x hoi. hieu van cham thuc day thanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ly) OR (sach lo)) nang x hoi. hieu van cham thuc day thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ly) OR (sach lo)) nang x hoi. hieu van cham thuc day thanh vi cua tre*.