I don't 100% know what this is referring to and I wouldn't wish a TagbackTV video upon anyone, but you're probably referring to the tricks used to increase the probability of certain villagers appearing in the campsite?
Hopefully I'm not misunderstanding- you essentially want to have all villagers on your island not include the target personality- the campsite's priorities are to give you villagers from a personality type you do not have and a villager you haven't seen in the camp yet. Therefore, with lots of time, you can cycle through every villager of the target personality and be guaranteed to see the villager you want once.