Maybe something like:

Sub findforms()
Dim cell  As Range
For Each cell In ActiveSheet.UsedRange.SpecialCells(xlFormulas)
If InStr(cell.Formula, "(") Then
MsgBox cell.Address
End If
Next
End Sub

then substitute what you are looking for in place of "("?

Worth a try. I use that form  to replace cells with formulas
with the values.