The phrase "certain individuals" refers to specific or particular people. It means that it's talking about particular individuals or a specific group of people, rather than everyone in general.
Sentences with «certain individuals»
Some coursework may be required for certain individuals who have not met all requirements. (certificationmap.com)
Perhaps in certain individual scenes, but it is a very minor complaint. (slantmagazine.com)
Another thing the film does well is tell the stories of certain individuals who were impacted. (moviereviewsfromthedark.com)