Is there a way to merge 2 conversations/emails of the same person into one thread?

Sometimes when an email is being assigned to my team and to many others as well, then I don't have the choice to assign it to all the rest of the groups so I have to choose only one, basically some emails do not refer to my department any more and I don't want to receive any other notifications. So all the rest of the 5 teams that have access - immediately lose it since I only have to choose one team to assign it.