I use 'Command-4' to select parts of documents (web pages for example) on a daily basis. Most of the times, I open several of those in one Preview windows. However, when it's time to save them in .pdf format, Preview saves only the first page (thumbnail) even if I select all the thumbnails in the sidebar. Is there a way to save multiple one-page files in only one (multiple-page) .pdf file? Thanks for your help.