Make VBA code shorter

Ok, I've been trying to make the code work, but when I put it in, all it would do was just flash the screen a couple of time and no surveys were pasted. I took the code appart and tested each part. The problem seems to be here:

'Paste LEFT to Data Sheet
    If Sheets("Data").Range("A4") = "" Then
        Sheets("LEFT").Range("A1:L1000").Copy Sheets("Data").Range("A4")
    Else
        Sheets("LEFT").Range("A1:L1000").Copy Sheets("Data").Range("A" & Rows.Count).End(xlUp).Offset(1)
    End If

'Paste RIGHT to Data Sheet
    If Sheets("Data").Range("A4") = "" Then
        Sheets("RIGHT").Range("A1:L1000").Copy Sheets("Data").Range("A4")
    Else
        Sheets("RIGHT").Range("A1:L1000").Copy Sheets("Data").Range("A" & Rows.Count).End(xlUp).Offset(1)
    End If

For some reason it doesn't paste any data to the data worksheet. I appreciate your help