Welcome to Steemit/Dtube!
If you know their usernames, you can type it into the actual menu bar. Check out the screenshot below to see what I mean. If I was looking for a particular user, I would just delete coruscate and put in their user name instead.
We are definitely still in beta testing! So sometimes things aren’t the most intuitive.
RE: How Dtube has Leveled the Playing Field for New Users