In the movie Harry Potter and the Order of the Phoenix, luna finally said, "What is lost will eventually come back to us". I don't understand English. Who can tell me?

What is lost will always find its way back.

Although the way back is always different from what we imagined.

Anyway, my mother always said ...

... there's always a way to lose something

Finally come back to us.

If it's not always the way we want it to be.