I understand that "jen" means "behold" or "here is" and I see it used often. But is it ever proper to use "tie cxi estas", and what's the difference between the two? When should I use "jen" and when should I use "tie cxi estas"?

I understand that "jen" means "behold" or "here is" and I see it used often. But is it ever proper to use "tie ĉi estas", and what's the difference between the two? When should I use "jen" and when should I use "tie ĉi estas"?