Outlook Rules Question

[Cheesecube]

Hi, I am currently using InStr to look for a String in another String

findRefund = InStr(1, "Refund order - Item code 10000000", "Refund", vbTextCompare)

But what if I want to use multiple search criteria, with capitalization variants?

E.g.

Refund
refund
Exchange
exchange
Return
return

Writing separate InStr lines for each criteria seems inefficient.

How do you search for all of these criteria using minimal code?