Have just done months trip around western Europe,after acouple of days in heavy rain,icalled in garage in france for some window spray for windows,they looked like mirrors when ide finished.driving along the next day the sun was out and when i tried to look through the window that the sun was coming through icouldnt see a thing it looked like id cleaned them with a dirty rag( smeared.) when there was no sun on a particular window it looked fine.HELP what shall i use to bring them back to new.ta