Can anybody help me that how to create new sub-menu that shown just from admin . any one can help me . Thank you in advance.
You can modify socialengine's engine4_core_menuitems table. For the correct menuitem you can create a submenu by filling "submenu" param of the needed menuitem. In "submenu" you should state menu name, of course. SocialEngine will do other things for you automatically, you only need to find proper admin menu and menu item to call submenu.