Thanks for sharing the details with us.
Sometimes it is about searching, you are right, but there is an indication of a mission giver being around on the people tab (the same icon you see in the ventures box on the lower right in case you play the desktop version). Thus, you "just" need to check the places until you find the area with the according icon.
Are you playing on Desktop or mobile (as mobile UI will be updated as our next step in summer)?
In our blog we shared a summary about the current & future dev roadmap.
Cheers!