‘CTRL+’ and ‘CTRL-‘ don’t work on iPad connected to PC. Anyone have a solution?

When using a windows PC remotely from my iPad I’m unable to send CTRL+ or CTRL- key combos used for zooming in and out in photoshop. Strangely enough, when I connect remotely to a Mac running OSX using my ipad I can’t send the ‘command +’ or ‘command -‘ key combos either. Another issue in photoshop is not being able to hold the space bar down to get the little grabber hand that pans around the image.

Anyone run into a similar problem? Fixes?