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:
 url: '/wp-content/themes/mo/include/front_page_part.php', 
 type: 'POST',
 dataType: 'html',
 success: function(data){
 error: function (data) { 

To treat a certain function, in this separate file I connect WordPress
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
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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