Hi, I had searched for this guide ad nauseam and had not found very promising information. But in the end I got the method, here goes:
Cold War Era
Just wait for some of your factions to offer missions and notice that if you reject them, they will create protests as a negative term that explains the same mission. Especially with communists and environmentalists who will demonstrate in the industry, I advise lowering those factions at least to send you missions that you can deny and get protests
Beware of protests, they are bugeados so you will need to save a game before rejecting faction missions to provoke protests. Once done if they do not appear as was my case, recharge the game until you see one, and try your luck 50 times with that or as in my case they started to leave gradually, so repeat this cycle until you complete the achievement.