I realize the rules could be clearer on this. Phase 1 Questing is you questing against any of the face up 5 Quest cards. Then you do the Shop card. Then you flip over the remaining 5 Quest cards to do Phase 2 Questing on the remaining face up 5 Quest cards.
You deal them face down so you don't know which Quest cards you have for the second set of Quests after the Shop card.
If it helps it acts like this:
Phase 1: Q Q Q Q Q
Shop
Phase 2: Q Q Q Q Q
Final Scoring
Thanks for playing!