push back one's vision

For example, travelling can push back your vision. Does it mean travelling can expand your horizons?

Push back can mean to delay, as in:

"I've had to push back our vacation due to the recent events."

So it could mean that the person's vision, or dreams, would be delayed by traveling, but the context isn't that clear to me.

I've never heard the phrase "push back your vision" used in that context before (or in any other context for that matter). I'm not sure what it means, but your guess sounds reasonable.