I have problem with php function : mysql_real_escape_string

My test string:

    @,&!#$%^*()_+' "\/

I add this data to mySql database, like that (in short):

    $str = mysql_real_escape_string($str);

    $sql = "INSERT INTO table(company) VALUES('".$str. "')";

In DB is stored as:

    @,&!#$%^*()_+\' \"\\/

But problem is with find this data by SELECT statement.

I want find, company where name is like

    ' "

My SELECT's:

    SELECT company FROM table WHERE company LIKE '%\' "%';
    SELECT company FROM table WHERE company LIKE '%\\' \\"%';

This works:

    SELECT `company` FROM `table` WHERE `company` LIKE '%\\\' \\\\"%';

    and

    SELECT `company` FROM `table` WHERE `company` LIKE  '%\\\\\\\' \\\\\\\"%'

But I dont know why this work :(.

My questions are:

• why must add so many slashes ?

• how I can make correct query in PHP:

    $query = '\' "';
    '%'.mysql_real_escape_string($query).'%' 
    result is : '%\' \"%'

    '%'.mysql_real_escape_string(mysql_real_escape_string($query)).'%'
    result is : '%\\\' \\\"%'

    '%'.mysql_real_escape_string(mysql_real_escape_string(mysql_real_escape_string($query))).'%' 
    result is : '%\\\\\\\' \\\\\\\"%'

Only last one works good.