>>900
検索範囲を変える必要がある

For x1 = 2 To 21
  Set cell = Cells(Int((x1 - 2) / 4) * 4 + 2, 2)
  z1 = Range(cell, cell.Offset(3, 0)).Find(What:="1", LookIn:=xlValues).Row
  z2 = Range(cell, cell.Offset(3, 0)).Find(What:="4", LookIn:=xlValues).Row
  Cells(x1, 3) = z1
  Cells(x1, 4) = z2
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