You can check this site on how to get fragments.. :lol
http://twinfinite.net/2016/07/naruto-online-how-to-get-ninja-fragments/

From this site above my post..
One of the ways to earn Fragments is simply by playing through the story. You’ll earn rewards for clearing an instance and these tend to include Fragments for one of the major characters of that instance’s story. For example, the first instance earns you Sakura Fragments, and the second one earns you 30 for Haku.

Another way to earn some Fragments is through the 7 Day Pack. Every consecutive day you log in, you’ll earn rewards, and for the second day onward, you’ll earn Fragments for numerous Ninja.