Mac Mail stacking contacts

Is there any way to stop Mail from stacking emails together from people with the same first name. See example below. Those are all in the same email chain when I open one, they're all there. I interact with a lot of different potential clients everyday and it's super confusing when all of the Mark's appear as one email. I see it's called the "Found in..." function. IS there a way to disable that?

See example below. Those are all in the same email chain. When I open one, they're all there just because they all share a first name. Please help.