Different printers process the display from a web site differently. My guess is that you are either trying to print the site in color or your printer driver is not capable of supporting the full graphical display of the web page. My suggestion is that you try to print the text pages out with your images turned off on your browser. If you continue having problems, you may want to check with your printer manufacturer and determine if you need to upgrade your printer's drivers or another part of your printer's configuration. When I try, all that prints is the headings of the topics and not all the content of the headings.
Different printers process the display from a web site differently.