Perhaps you should try some spelling variations:
tay quang » tac quang, tai quang, vay quang
tao quang » dao quang, hao quang, lao quang
toc sach » hoc sach, doc sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
dan vai » dan tai, dan vat, den vai
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
dan va » doan va, dan ca, ban va
va nam » van nam, ha nam, va nay

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 quang) or (tao quang)) ma hoa. hieu va nam thuc va ((dan vai) OR (dan va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tay quang) OR (tao quang)) ma hoa. hieu va nam thuc va ((dan vai) OR (dan va)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((tay quang) or (tao quang)) ma hoa. hieu va nam thuc va ((dan vai) OR (dan va)) cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((tay quang) or (tao quang)) ma hoa. hieu va nam thuc va ((dan vai) OR (dan va)) cua tre*.