How to retrieve text only from wp_content() not from wp_excerpt()?

Or even simpler:

echo wp_strip_all_tags( get_the_content() );

By using:

• get_the_content()
  

  Retrieve the post content. (Must be used in a Loop)

  An important difference from the_content() is that get_the_content() does not pass the content through the ‘the_content‘. This means that get_the_content() will not auto-embed videos or expand shortcodes, among other things.

• wp_strip_all_tags()
  

  Properly strip all HTML tags including script and style.