Invite friends facebook sdk unity android

Hello,

I m developing an android application. I can login to facebook and retreive username,id and user profile picture and i can invite friends. I can check all the friends that i have and invite them to my application using facebook sdk for unity. Everything works fine. But the problem that i want just to pick 5 friends from my facebook friend's list and invite them to my application. Can you help me please. Thanks in advance