How to mix 2 keying nodes in the compositor to keep the alpha channel from both? How do I mix two keys in the compositor to form an image that uses both the keyed out parts?  Movie Clip node > Keying node > Viewer = green screen removed; then same Movie Clip node > different Keying node > Viewer = blue markers removed.  How do I combine these?  I am trying to remove the background, and isolate the people in the foreground and have an alpha channel background.

edit: I don't really know what to search for, can anyone maybe share a link or just tell me the words to search for in Google?

Do I need to render out 1, then go back and re-render out the second?  I feel like there is a way, similar to render layers, but with images/movies, sorry if this doesn't make sense, I will edit it when I can.
put one into the other as so - that way each node changes the previous