1. Remember to revisit old locations frequently. Something may have changed, often in a subtle but important way.
2. Don't forget to talk to everyone about everything. You never know who may have information you need. And Mahrute especially is—almost—always there to help.
3. If a topic sounds like it has more to it during a conversation, or something new has happened since you last spoke, don't hesitate to bring it up again. There may be more information coming.
4. Don't forget to tap items in your inventory to examine them. Tapping their close-up gives you a comment—it may be useful.