Perhaps you should try some spelling variations:
theo thuoc » che thuoc, tao thuoc, thu thuoc
thuoc sach » hoc sach, nuoc sach, thuat sach
thong cong » trong cong, tong cong, thong thong
hung hang » hung thang, hang hang, khung hoang
va thong » va thuong, va phuong, he thong
san toan » van toan, manh toan, xuan toan
dan toan » van toan, dan than, manh toan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo thuoc sach - hung hang va thong cong ((san toan) or (dan toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo thuoc sach - hung hang va thong cong ((san toan) OR (dan toan)) cau.
• Adding a wildcard symbol may retrieve word variants: theo thuoc sach - hung hang va thong cong ((san toan) or (dan toan)) cau*.