Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
van thanh » ban thanh, van tuan
toc sach » hoc sach, thuoc sach, nuoc sach
thanh vi » hanh vi, thanh va, thanh ve
doc sach » hoc sach, nuoc sach, dac sac
lang van » dang van, tang van, hoang van
thuc van » thuc vat, thuc dan, thuc va
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va
y lang » o lang, _ lang, tay lang
vi cua » vai cua, di cua

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) or (doc sach)) y lang van hoa. ((hieu va) or (hieu qua)) cham thuc van thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) y lang van hoa. ((hieu va) OR (hieu qua)) cham thuc van thanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) y lang van hoa. ((hieu va) or (hieu qua)) cham thuc van thanh vi cua tre*.