Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
nang xa » lang xa, nang ma, mang xa
van cam » van nam, van lam, van cau
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
xuc va » duc va, tuc va, luc va

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 thien ((nang xa) or (nang x)) hoi. hieu van cam xuc va hanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach thien ((nang xa) OR (nang x)) hoi. hieu van cam xuc va hanh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: thu sach thien ((nang xa) or (nang x)) hoi. hieu van cam xuc va hanh vi ((cua tre) or (cuu tre))*.