Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
tinh vai » tinh va, tinh hai, tinh bai
thuoc xa » thuoc ma, thuoc va, thuoc la
so sach » so sanh, bo sach, co sach
cua tre » cua te, cua triet, dua tren
xa tinh » va tinh, ha tinh, ca tinh
cuu tre » cau tren, cau treo
hieu va » lieu va, hieu qua
ly hang » ly quang
lo hang » le hang, cho hang, le thang
va hoi » xa hoi, va hoc, va hoa
va nam » van nam, ha nam, va nay

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 ((lo hang) or (ly hang)) va hoi. hieu va nam thuoc xa tinh vai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((lo hang) OR (ly hang)) va hoi. hieu va nam thuoc xa tinh vai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((lo hang) or (ly hang)) va hoi. hieu va nam thuoc xa tinh vai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: so sach ((lo hang) or (ly hang)) va hoi. hieu va nam thuoc xa tinh vai ((cua tre) OR (cuu tre))*.