The reason for the error 404, when Ajax query wordpress?

The page is very heavy, load the first screen, then connect the rest of the page. It I made in a separate file. Connection:
$.ajax({
 url: '/wp-content/themes/mo/include/front_page_part.php', 
 type: 'POST',
 dataType: 'html',
 success: function(data){
$('.body_internal_page').append(data);
},
 error: function (data) { 
console.log(data.error);
console.log(data);
}
 });

To treat a certain function, in this separate file I connect WordPress
require('../../../../wp-blog-header.php');
So, if VP is connected, the server returns a 404 error, although the "response" I see all the html code which you want to connect, naturally in the page it is not inserted.
If you remove
require('../../../../wp-blog-header.php');
The main part of the page is safely loaded. Actually the question why wp gives me a 404?
June 26th 19 at 14:13
0 answer

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