After checking your site we found issue come from permalink setting or .htaccess file cause this issue: http://prntscr.com/lknbwj
It make ajax can’t load more video items.
Did you have some special config because it alway have index.php on url like this: http://osmanthewho.com/index.php/my-work/
Other reason maybe come from stranger plugin not required in our theme.
Please check it!