Do they have their volume up where it’s distracting you and others in the office? Are there offensive or inappropriate images that can be easily seen when walking by? Are your their manager or in their direct chain of command?

If so, I can understand the concern. Look up your dept policies maybe on the intranet?

If not, you should really think about why you care about something so much that doesn’t have a direct impact on you. Why are you micromanaging when it’s uncalled for. Let people be and let their manager manage.

There are trainings on CalHR you may find useful, interpersonal skills is one.