Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, hieu ve
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
cau luc » cau truc, cau phuc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ma hoi. ((hieu van) or (lieu va)) cau luc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ma hoi. ((hieu van) OR (lieu va)) cau luc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ma hoi. ((hieu van) or (lieu va)) cau luc va hanh vi cua tre*.