Well Im not sure of the context of what you quoted, but it can mean one of two things:
The Seforim say that there are parallel realities in existence. Just as in the Torah there are 4 parallel ways to understand each idea - Pshat, Remez, Drush, and Sod, so too there are 4 parallel worlds, each one with its own reality.
For example, the Gemora (Taanis 5b) says Yaakov Avinu never died. Then it asks how could that be - they buried him! The Gemora answers מקרא אני דורש שנאמר וגו. There are those who explain this to mean that in the simple world of Pshat Yaakov died and was buried but in the world of Drush he remained alive.
Or it could mean what I explained here
One of the two.