XML Content inside page not displaying except title of page

Dear Experts,

I have a XML view with Page tag ,content inside <Page></Page> is not displaying except title of the Page.

But When I place all <Page></Page> inside <App></App>( like this <App><Page></Page></App>) it is displaying everything inside page exactly what I want.

May I know the reason for this or concept behind this.

View code and output before adding <App> tag:

View Code and Output after adding <App> tag:

Thanks,

venkatesh.