$sql = mysql_query("SELECT * FROM 
         patient_db WHERE 
         MATCH ( Name, id_number ) 
         AGAINST ('+first_word +second_word +third_word' IN BOOLEAN MODE);");

，如果您想进行精确搜索:

and if you want to do exact search:

$sql = mysql_query("SELECT * 
                  FROM patient_db 
                  WHERE MATCH ( Name, id_number ) 
                  AGAINST ('"exact phrase"' IN BOOLEAN MODE);");