When you try to find a place you have heard of within Hogwarts roll + INT on a hit you find it before you are needed elsewhere. On a 10+ you discover some new facet of the castle. On a miss you are called away before you can find it. Someone is upset with you.
When you rush through the halls of Hogwarts to find or lose someone roll + CHA. On a hit you catch or lose them. On a 10+ you do so in a timely manor. On a miss you get caught or lose your quarry and the GM may make a Hard Move against you.
When you wander the halls of Hogwarts aimlessly roll + WIS. On a 10+ your GM will offer you a Golden Opportunity. On a 7-9 you are unbothered in your perambulations. On a miss you open yourself up to a Hard Move.