Range.Find with merged cells

I keep getting completely random results using the .find method with a sheet containing merged cells:

I've tried all combinations of
xlpart, xlwhole
xlvalues, xlformulas
expanded the range to include the merged cells
set range as all column A, column A & B

but I can't get it to work consistently, if at all.

I could get it to work if I searched the whole sheet without specifying a range, however there are likely to be more instances over time so I don't want it to find them as it will screw up the range.

I know merged cells are an absolute pain, however they need to remain that way in this case.

Thanks

Little amendment to your code

With r
    Set acell = .Find(What:=thisyr, LookIn:=xlValues, LookAt:=xlWhole)
    
     If Not acell Is Nothing Then
       Debug.Print acell.Address
     End If
End With

You also need to format your dates to year or month. The code will not find 12 or 2015.

Merged cells are paid in the a**. The only way I can get to work this code is:
First unmerge cells, find the value (Address) and then once you are done, you can re-merge them.

Option Explicit
Sub cellfind()

Dim dws As Worksheet
Dim r As Range, acell As Range
Dim dte As String
Dim thismth As Date
Dim thisyr As Date
Dim dlastrow As Long

thismth = Month(Date)
thisyr = Year(Date)

Set dws = Sheets(1)

dlastrow = dws.Cells(Rows.Count, "B").End(xlUp).Row
Set r = dws.Range(dws.Cells(1, 1), dws.Cells(dlastrow, 2))
Debug.Print dws.Cells(1, 1).Value
Debug.Print r.Address

With Columns("A:B")
    Range(.Cells(1, 1), .Cells(1, 2)).UnMerge
    Set acell = .Find(What:="2015", LookIn:=xlValues, LookAt:=xlWhole)
    
     If Not acell Is Nothing Then
       Debug.Print acell.Address
     End If
     
     
      Range(.Cells(1, 1), .Cells(1, 2)).Merge
End With


End Sub