Hi beatcoach,
Unfortunately it's not currently possible to search for a specific kind of repeat interval. As you mentioned, you can find all tasks that are repeating, but you're not able to narrow it down further. Sorry for any inconvenience.

In the meantime, you may want to vote for this suggestion in our Ideas forum here.

Thanks!

It seems that rtm can do so much that I was surprised when I tried to search for daily repeating tasks and couldn't do it. That's how I ended up here. Guess I'll have to work around it somehow. Or not.

In the past I had to tag the repeat items (using daily, weekly, etc.) and then make an appropriate smart list using the tag.