Creating a look up table

Hello

I have a problem during creating a lookup table. I have to map some text to something else. For example LookUp{" Hello World"} = " Ok Hello";

My question is how do I map if there is a comma between Hello and World i.e Hello, World

LookUp{"Hello, World"} = "Ok Hello"; doesn't work. I am a novice, please help.

re: Creating a look up table

The comma is no problem:

So the problem is elsewhere in your code, that we can't see.