Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
cac thuc » cach thuc, cac thu, can thuc
doan vi » doan va, don vi, doan thi
sach tu » sach thu, sach ty, sach uu
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
hang xa » hoang xa, hang va, hang ca
cach tu » cach thuc
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach tu) OR (cach tu)) hang xa hoi. hieu ve cac thuc dan ((ban va) or (doan vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tu) OR (cach tu)) hang xa hoi. hieu ve cac thuc dan ((ban va) OR (doan vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach tu) OR (cach tu)) hang xa hoi. hieu ve cac thuc dan ((ban va) or (doan vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach tu) OR (cach tu)) hang xa hoi. hieu ve cac thuc dan ((ban va) or (doan vi)) cua tre*.