Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thu hang » thi hang, thuc hanh, thu huong
thi nang » thi cong, ki nang, thi hanh
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
van cam » van nam, van lam, van cau
tu sach » thu sach, su sach, te sach
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: tu sach ((thu hang) or (thi nang)) xa 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: tu sach ((thu hang) OR (thi nang)) xa hoi. hieu van cam xuc va hanh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ((thu hang) or (thi nang)) xa hoi. hieu van cam xuc va hanh vi ((cua tre) or (cuu tre))*.