Perhaps you should try some spelling variations:
thien van » thi van
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc 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: tu sach ky ((lang xa) or (nang ma)) hoi. ((hieu ve) or (thien van)) cam xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((lang xa) OR (nang ma)) hoi. ((hieu ve) OR (thien van)) cam xuc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((lang xa) or (nang ma)) hoi. ((hieu ve) or (thien van)) cam xuc va hanh vi cua tre*.