How does find my air pods actually work

I’ll just share my story with my question. So today I went to the mall to buy some clothes. I went to the fitting room to try them on and went outside to show my fiancé to see what she thought. In that time someone went into the fitting room I was using and went through my jeans and took my old iPhone 7 Plus that is just for music, and my air pods. I check the find my app and saw that both iPhone 7 and air pods were on the move. As we decided what to do either wait for police or keep tracking them, I decided to track them before they go offline and are gone for good. This person had a good head start but I was still able to track them down despite him being blocks away. He was so far away that we had to drive to catch up while he was on foot. How was that possible, my understanding was you needed some type of internet connection or be near my phone to get a location. But this person was really far away but yet my iPhone that had no cell service or wifi was still being tracked. Do air pods work like air tags and ping other iPhones to get their location? And since my iPhone was near my air pods that is how that was also able to be tracked? My cuestión is basically how does the technology work?