Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
thuc day » thuc dan, thuc vat
tay lang » tai lang, tay tang, tay quang
sach tay » xach tay, sach hay, sach nay
doan vi » doan va, don vi, doan thi
thue va » thuc va, thuyet va, thuc vat
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ve cac » va cac, vien cac
dan va » doan va, dan ca, ban va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach tay lang xa hoi. hieu ve cac ((thuc day) or (thue va)) ((dan va) or (doan vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach tay lang xa hoi. hieu ve cac ((thuc day) OR (thue va)) ((dan va) OR (doan vi)) cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach tay lang xa hoi. hieu ve cac ((thuc day) or (thue va)) ((dan va) or (doan vi)) cua tre*.