Because each variable is available to all the commands, they will update all the graphs at the same time.
From the parameter set that is showing, it looks like you want the first graph to have kp4 as the only one changing. I suggest modifying the Function commands to change what variable is being used. For example, instead of using (RIA_inf1, RIA_inf2, RIA_inf3, and RIA_inf4) all the first graph, and set to the same value, only use RIA_inf1, in all four Function commands. Then use RIA_inf2 in your second graph for all the Function commands, with a different value, etc.
I would also encourage you to try a Slider variable to vary one parameter. If this is for print, that may not be useful, but for exploring function dynamics, they can be very helpful.
Hope that helps, there is also a way to have your variable values in the data table and pull then using a Number from column variable where you vary the index. That could be helpful if you want to explore lots of combinations, but then I think the sliders are a lot easier.