Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
hieu ve » hieu van
dang ma » dang mau, dang mam, dang mat
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky dang ma hoi. ((hieu ve) OR (hieu va)) cam ((xuc va) or (tuc va)) hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky dang ma hoi. ((hieu ve) OR (hieu va)) cam ((xuc va) OR (tuc va)) hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky dang ma hoi. ((hieu ve) OR (hieu va)) cam ((xuc va) or (tuc va)) hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky dang ma hoi. ((hieu ve) OR (hieu va)) cam ((xuc va) or (tuc va)) hanh dai cua tre*.