Exclude categories from blog page

Hi Everybody!

I want to exclude some categories from my blog page: https://www.billigste-internet.dk/blog/. Is about “Anmeldelse”, “Mobilt bredb?nd” and “Bredb?nd”.

So I have added the following code before The Loop.

<?php query_posts($query_string . '&cat=-9,-6,-5'); ?>

But the post are their still (look here: https://www.billigste-internet.dk/blog/page/4/). What should I do to exclude this categories?

Hope someone can help me ??