You can decide who should access your content by limiting access to a particular group for a content. This will allow to make a content available for a set of people and other will not be able to access that content. By default access rights are given to only admins and librarians when nothing is selected in access rights. If you want only group A should access the content, remove the existing group and add group ‘A’. You can create group from settings. The other way to do is through the Bulk actions, you can select all the contents for which you want to change the access rights and click on Bulk actions and select manage access rights. You can grant and revoke access from here. Also, when you move any content from your mywork to public folder, make sure to check the access rights and manage it, if you do not give access to anyone then only admins and librarian will be able to view your content. To check the steps, please refer to the mentioned link.