When you open Find My, it will display information that is available at the time.
If the phone is not found.....Find My has not been enabled on the iPhone that you are looking for.
If "Offline" is displayed......there are several reasons why this might occur:
- The battery has run down
- The phone has been powered off
- The phone does not have an Internet connection where it is currently located
In cases of theft, thieves are very fond of placing a phone in a special type of bag that will not allow the phone to either send or receive a signal. Obviously, an update on the location of the phone is not possible in this very common situation.