Many different airplanes feature two small sticks on both sides of chart holders. These can be moved within a limited range. I've heard different versions about their use and haven't found any documentation regarding them.
You aren't going to find any documentation from the Learjet 45 AFM or PM. They allow the pilot with paper charts to adjust the angle of the chart so the pilot can read it easier while flying. There is no other purpose for those extra "small sticks"