read more function is not working

Dear all,
I was tryling to publish my articles to different pages, however, read more function is not workign at all, I did everything I could, I read your forums and modifed the_content in somewhere, and I also modified page.php also, I tried to modify even finctions.php, I also uploaded “read more” plugin, but none of them worked, please help me with working, any help would be greatly appricited