Keen mind of the Detective

You have spend most your life putting 2 and 2 together based on information you gather. You now have the ability to roll for "Observe", this will be the same as investigation+proficiency bonus. When learning 2 separate pieces of information regarding the goal specified by you, you may roll a observation-check. On a success (determined by DM) you receive one clue(also determined by DM) regarding how to determine a conclusion about the final goal of your train-of-thought. You may roll one observation-check once a day, resetting after a long rest