Sub thaydoi()
Dim arr
Dim dic As Object
Dim a As Long, lr As Long, i As Long
Dim dk As String
Set dic = CreateObject("scripting.dictionary")
With Sheet1
lr = .Range("D" & Rows.Count).End(xlUp).Row
If lr < 4 Then Exit Sub
arr = .Range("D4:E" & lr).Value
For i = 1 To UBound(arr, 1)
dk = Trim(arr(i, 1))
If Not dic.exists(dk) Then
dic.Add dk, arr(i, 2)
End If
Next i
lr = .Range("b" & Rows.Count).End(xlUp).Row
If lr < 4 Then Exit Sub
arr = .Range("A4:B" & lr).Value
For i = 1 To UBound(arr, 1)
dk = Trim(arr(i, 2))
If dic.exists(dk) Then
arr(i, 1) = dic.Item(dk)
End If
Next i
.Range("A4:B" & lr).Value = arr
End With
End Sub