How do you explain thinking about someone and then having them pop into your life again ? Is it just coincidences ?

Have you ever been thinking about someone in particular, and then boom, they show up back into your life, or you hear from them? Or how about thinking about someone, and you bump into them suddenly, or get a call from them. Is it just coincidences? Is it something psychic instead. What happens if this has been happening a lot – to the point where it can’t be just coincidence anymore?