Perhaps you should try some spelling variations:
hanh tri » thanh tri, hanh tai, hanh trinh
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu van
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » tuc va, luc va, xac va

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