Discover all 5 fragments / shards by finishing the following jobs, then talk with Trunks.

Defeat Mission 3 in the Demigra Saga.
Talk to Recon Time Square.
Complete Parallel Mission 49.
Defeat Goku in Parallel Mission 14 or beat Ginyu in Goku's body throughout Parallel Mission 18.
Complete Parallel Mission 2 or beat Super Saiyan Goku in Parallel Mission 21.