Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu va » lieu va, hieu qua
nam xuc » cam xuc, nam xua, nam thuc
ma hoi » mai hoi, ma hoa, me hoi
va nam » van nam, ha nam, va nay
y sang » _ sang, duy sang
xuc va » duc va, tuc va, luc va
va dan » ca dan, va dap, va dai
va dao » ca dao

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 sang ((ma hoi) or (xa hoi)). hieu va nam xuc va dan ((va dau) OR (va dao)) treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y sang ((ma hoi) OR (xa hoi)). hieu va nam xuc va dan ((va dau) OR (va dao)) treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y sang ((ma hoi) or (xa hoi)). hieu va nam xuc va dan ((va dau) OR (va dao)) treo".
• Adding a wildcard symbol may retrieve word variants: thu sach y sang ((ma hoi) or (xa hoi)). hieu va nam xuc va dan ((va dau) OR (va dao)) treo*.