How to follow people from other instances?

I want to follow https://mastodon.social/@haskelldiscussions, but I can't seem to reach them from kbin. Usually with mastodon, I believe I should be able to search for that URL, like this:

https://kbin.social/search?q=https%3A%2F%2Fmastodon.social%2F%40haskelldiscussions

But that does not give any results. I've also tried looking up the user directly like this:

https://kbin.social/u/@haskelldiscussions@mastodon.social

But that also does not work.

Is there any way to do this?