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