I have just checked in a repair manual for a 2009 > 2014 VW Polo, and to remove the air cleaner from the 1.4 engine, after you have removed the top and filter element, pull off any hoses that you can see, then pull up the air cleaner box away from its fixings, once free from them, unclip a fuel hose that is fixed to its underside.
I seem to remember reading that some of the cars with that engine, needed to get their O-rings replaced while under warranty, so a known issue to VW Group.