Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach thu » sach thue, sach thieu, sach tham
cham xuc » cam xuc, chat xuc, cham soc
hieu sau » hieu su, hieu suat, tieu su
hieu vu » hieu va, hieu ve, hieu su
thu ban » thu hang
va luan » vay luan, van luan, va quan
cua tre » cua te, cuu tre, cua triet
tu sach » thu sach, su sach, te sach
ban xa » ban va, ban ma, ban da
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 ban xa hoi. ((hieu vu) or (hieu sau)) cham xuc va luan van ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu ban xa hoi. ((hieu vu) OR (hieu sau)) cham xuc va luan van ((cua tre) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: tu sach thu ban xa hoi. ((hieu vu) or (hieu sau)) cham xuc va luan van ((cua tre) or (cua viet))*.