What does "tune into" mean?

That he is clarvioant. Edit. That he understands above average with his intuition.

He’s intuitive. But in the same video the lady says sometimes it doesn’t work out. This time it did.

Focus attention on.

We used to say, ‘tune in’, specifically for when we turned our old fashioned radio dials to a station so we could receive the radio signal and listen to that station. Now, we use it as an expression meaning to pick up any signal, be it radio, paying attention to fashionable trends, or emotions coming from a person, etc. Does that help?

The other posters are correct about the meaning of the phrase, but it should always be written as “tune in to,” not “tune into.” This is an increasingly common error.