[Admin]

In search.php replace:

    $datesql=" AND thread.lastpost>=".$bbuserinfo[lastvisit];

    $wheresql="1=1".$forumsql.$datesql;

with:

    $datesql=" AND thread.lastpost>=".$bbuserinfo[lastvisit];

    $wheresql="1=1".$forumsql.' AND forumid NOT IN (3,6,7,23) '.$datesql;

Now it will ignore forumd 3, 6, 7, and 23.