What's your method to find Raids?

I go sometimes four days before I find. It sucks but nothing can be done, I guess.

I grind on frozen 3. Decent exp, guaranteed chests on a roll of 5 n 6 from the start, there also a shop if you get lucky. I meet a boss every 1-2 days

Well I find all my raid bosses within 5-10 mins... Volcano 10 and Sea 10 Normal.. All this week I've found my raid boss within the first 2 minutes of searching for it. Those two spots are my sweet spots.