Blank prints when printing docs/photos

Your printer is a little different than most of the current ones on the market today in that your ink cartridges only contain ink; they don't have a printhead integrated into them. That of course makes them substantially cheaper, but the downside is that you don't get a new printhead whenever you buy a new cartridge.

Your Canon has a single printhead built into the carriage that holds the ink cartridges, and the good news is that it's made to be almost as easy to replace as the ink cartridges. This video shows you how.

DIY Printhead replacement for Canon MX922 printer - YouTube

The online manual for your printer suggests the following steps if it's not printing.

Print the Nozzle Check Pattern to determine whether the ink ejects properly from the print head nozzles.

• If the Nozzle Check Pattern is not printed correctly:
  Check to see if a particular color's ink tank is not empty.
  If the Nozzle Check Pattern is not printed correctly though ink is sufficient, perform the Print Head Cleaning and try printing the Nozzle Check Pattern again.
• If the problem is not resolved after performing the Print Head Cleaning twice:
  Perform the Print Head Deep Cleaning.
  If the problem is not resolved after performing the Print Head Deep Cleaning, turn off the machine and perform another Print Head Deep Cleaning after 24 hours. When you turn the machine off, do not unplug it from the power supply.
• If the problem is not resolved after performing the Print Head Deep Cleaning twice:
  If Print Head Deep Cleaning does not resolve the problem, the print head may be damaged.
  Contact the service center.

Given your description, I doubt this will help, but outside of wasting ink, it won't hurt to try. If that doesn't work, then I'd be out shopping for a new printhead, myself. An online search for "Canon QY6-0086 printhead" should give you many choices to pick from; choose one that fits you for price and availability. You could try removing the printhead and soak it in 90% or higher concentration isopropyl (rubbing) alcohol to see if that opens up the print nozzles; I've had mixed results with that myself; sometimes it helps and other times it doesn't.