Another solution on condition the records are already in the form's recordset (does not matter whether it is single view, continuous view, datasheet view) and you want to jump to a particular one.
Private Sub SearchButton1_Click()
dim rsTemp as Recordset
If IsNull(Me.SearchField1)=False Then
Set rsTemp = Me.RecordsetClone
rsTemp.FindFirst "[UniqueAEVRef] = '" & Me.SearchField1 & "'"
If Not rsTemp.NoMatch Then
Me.Bookmark = rsTemp.Bookmark
MsgBox "No record found", vbOKOnly + vbInformation, "Sorry"
One remark: code above assumes field UniqueAEVREF is defined in its table as a textfield. In case the field type is number, you must use next line
rsTemp.FindFirst "[UniqueAEVRef] = " & Me.SearchField1
If it is a datefield, it becomes
rsTemp.FindFirst "[UniqueAEVRef] = #" & Me.SearchField1 & "#"