OK! I am successfully filtering now 
One more question for the moment. I am trying to make sure all my data elements show up, and then filter only when someone types into a text box. I believe it is very similar to this post:
But how would I write the expression for contains() or fuzzymatch() in the Filter parameter of the data view properties? I think if I can do this, I should be all set!
This is my current code, but I get this error in the console:
Formatter lowercase in expression [user.id.lowercase().contains(text1.value)] doesn’t exist for type string