Running Multiple Rspec Test metadata

I am trying to run multiple tests in Rspec using metadata tags. I usually run test like, RSpec -t case_id:1234, THis works fine however, I want to be able to run multiple case_ids. I tried methods like RSpec -t case_id:1234, case_id:4321 and -t case_id:1234 && -t case:id:4321 this just make two separate test run creating two separate environments. I want both tests to be able to run in the same environment.