here is the request : get all post from category=11 (get 21 post), and then in the 21 post got from this category, refilter it, and show only post from category=10. So the request should be : cat=11&10. i what post that are from BOTH category at the same time, because my category are job and active. i what the listing of all the job, and then show just the one that are ative in the system !
$$mycat = "11&10" $showPostsInCategory->query('cat='. $mycat.'&posts_per_page=-1');