IndexOfAny issue

Developing a page with asp.net (vb) and I am getting an error using an .IndexOfAny when I use a string but when just characters it works fine

My code is:

VB Code:

Dim sPhrase as String
Dim sList() as String = {" AND ", "OR"}
sPhrase = "John AND Mary"
 
lblPhrase.Text = sPhrase
 
If sPhrase.IndexOfAny(sList) = 0 Then
  lblResult.Text = "Not Found"
Else
  lblResult.Text = "Found"
End If

The following gives the following error:
BC30332: Value of type '1-dimensional array of String' cannot be converted to '1-dimensional array of Char' because 'String' is not derived from 'Char'.

If I change the following line:
Dim sList() as String = {" AND ", "OR"}

to

Dim sList() as Char = {"a", "e"}

Things seem to work fine. Is it not possible to search and array of strings with the IndexOfAny?

Thanks.