Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach tay » xach tay, sach hay, sach nay
nam thuc » nam thuoc, am thuc, nam thu
lang ha » long ha
lang xa » dang xay, lang van
hieu va » lieu va, hieu qua
thuc ca » thuc cua, thuc can, thuc cao
dan vai » dan va, dan tai, dan vat
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay
ca dan » cac dan, ca dao

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 tay ((lang xa) or (lang ha)) hoi. hieu va nam thuc ca dan vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tay ((lang xa) OR (lang ha)) hoi. hieu va nam thuc ca dan vai cuu tre.
• Adding a wildcard symbol may retrieve word variants: toc sach tay ((lang xa) or (lang ha)) hoi. hieu va nam thuc ca dan vai cuu tre*.