Wp query show post by author name or post title or post content

Question

I hope this would do, i have not tested it. Test it on your own risk, but the query related to it very closely.

function kv_get_custom_search_query($search_text){
   global $wpdb;
   $wpdb->get_results( "SELECT * FROM $wpdb->posts WHERE post_title="%$search_text%" OR post_content="%$search_text%" OR post_title="%$search_text%" LEFT JOIN $wpdb->users ON $wpdb->posts.post_author=$wpdb->users.ID AND display_name="%$search_text%"");

}