In in's Creed it says to climb a viewpoint to find investigations and it's not helping me. Any advice?

I'm supposed to talk to the burea leaders in damascus jerusalem and acre and they won't talk to me unless I have completed 3 of 6 investigations. I know that inves. include pickpocket, interrogation and eavesdropping but the levels are big and I can't find them easily. Even though it tells me to find them by climbing a viewpoint, I do so and I still can't find ou where they are. Any advice???