Hide panel formula for drop down field for multiple choices

I have a form that uses a Report Type field to hide a part of the form based on the selection.

Compliance

Walkthrough, Testing and Assessment

Walkthrough, Testing and Assessment with Compliance

Testing

Compliance is the Default.  The form should be hidden if either Walkthrough type is selected.

I have gotten the formula to work with 1 selection, but not if either is selected.

Report Type!='Walkthrough, Testing and Assessment'

works as expected, but I have not been able to get the "or" formula to work.  I tried:

Report Type!='Walkthrough, Testing and Assessment'||

Report Type!='Walkthrough, Testing and Assessment with Compliance'

this doesn't work.  I also tried:

Report Type!='Walkthrough, Testing and Assessment'||'Walkthrough, Testing and Assessment with Compliance'

I thought about using the Contains function, but I'm not sure how to create the formula.

Any suggestions?

Thanks

Cheri