Changes to published profile content won't display in the directory right away. The system refreshes the directory once per day, around 2 or 3am. During this refresh, changes that you make to user profiles which populate in published profile fields being pulled into the directory will update and display the next day.
If it's been more than 24 hours since you've added new content, check the Profile Publish Access settings. Platform Managers can access these settings via Core > Security > Profile Access > Profile Publish Access. There you can determine the roles to which each type of user can publish their profile information in the directory. Profile Relationship Access settings allow you to determine who can view and edit user profile information for each type of user. (You can find these settings via Core > Security > Profile access > Profile Relationship Access)