Merging 2 different instruments onto one staff

I wasn't able to find what I needed to help me with this, but I want to merge two different instruments onto one staff all together, I wasn't able to do instrument changes, and I could not find something that play those two instruments unlike how a drum set would give you different percussion instruments in one. I'm just looking for help on this, how it's set up is that I'm using bells, and vibraphone, I just want to add them in the same measure, how would I do that?