Perhaps you should try some spelling variations:
thanh ca » thanh cha, thanh cac, thanh ha
toc sach » doc sach, thuoc sach, nuoc sach
va thanh » gia thanh, ban thanh, va tinh
hoc sach » hoc sinh, hoc cac, hoc anh
cac thuc » cach thuc, cac thu, can thuc
tang van » dang van, hoang van, trong van
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
van hoi » van hoa, van hoc, van hoe
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
ca cua » co cua

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) or (((toc sach) OR (hoc sach)))) ky tang van hoi. hieu ve cac thuc va thanh ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (((toc sach) OR (hoc sach)))) ky tang van hoi. hieu ve cac thuc va thanh ca cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (((toc sach) OR (hoc sach)))) ky tang van hoi. hieu ve cac thuc va thanh ca cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (((toc sach) OR (hoc sach)))) ky tang van hoi. hieu ve cac thuc va thanh ca cua tre*.