Perhaps you should try some spelling variations:
cac thuc » cach thuc, cac thu, can thuc
thanh ha » thanh hoa, thanh hai, nhanh ha
toc sach » hoc sach, doc sach, thuoc sach
thanh ca » thanh cha, thanh cac, thanh va
tang van » dang van, hoang van, trong van
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
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) or (toc sach)) ky tang van hoa. hieu ve cac thuc va ((thanh ca) OR (thanh ha)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) ky tang van hoa. hieu ve cac thuc va ((thanh ca) OR (thanh ha)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (toc sach)) ky tang van hoa. hieu ve cac thuc va ((thanh ca) OR (thanh ha)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky tang van hoa. hieu ve cac thuc va ((thanh ca) OR (thanh ha)) cua tre*.