Perhaps you should try some spelling variations:
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va, hieu van
cuu tre » cau tren, cau treo
nang o » nang co, nang ho, nang ro
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, luc va
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((sach ky) or (sach y)) nang o hoi. hieu ve cam xuc va hanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ky) OR (sach y)) nang o hoi. hieu ve cam xuc va hanh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: so ((sach ky) or (sach y)) nang o hoi. hieu ve cam xuc va hanh vi ((cua tre) or (cuu tre))*.