Hello,
The free theme currently only has limited number of social link options .
If you like you can either build a child theme, and customize the theme to make more social links:-
To see how to make child theme check https://codex.wordpress.org/Child_Themes
OR you can use the pro version of this theme which has most of the links you require and more awesome features.
To see about the pro theme check
http://themepalace.com/downloads/amazing-blog-pro/
Best regards.