Sub TestNewCode()
Application.ScreenUpdating = False
Dim varMainRange As Range
Dim varSubRange As Range
Set varMainRange = Range(Worksheets("Jul").Range("A2:C65536"), _
Worksheets("Jul").Range("A65536").End(xlUp))
For Each MainCell In varMainRange
    Set varSubRange = Range(Worksheets("Data").Range("A2"), _
    Worksheets("Data").Range("A65536").End(xlUp))
    For Each SubCell In varSubRange
        If MainCell.Value = SubCell.Value Then
    Worksheets("Data").Range("A2:C2").Copy _
    Worksheets("Jul").Range("E2:G2")
            Exit For
        End If
    Next SubCell
Next MainCell
Application.ScreenUpdating = True 
End Sub

Sub TestNewCode()


    Const Tabs As String = "Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec"

    Dim WsData As Worksheet
    Dim Ws As Worksheet                             ' any of the monthly sheets
    Dim WsName() As String
    Dim Rend As Long, Rl As Long                    ' last row in WsData / Ws
    Dim R As Long, Rm As Long                       ' row counter WsData / Ws
    Dim Entry As Variant                            ' one Data entry

    Set WsData = Worksheets("Data")
    WsName = Split(Tabs, " ")
    Application.ScreenUpdating = False
    With WsData
        Rend = .Cells(.Rows.Count, "A").End(xlUp).Row
        For R = 2 To Rend
            Entry = .Range(.Cells(R, 1), .Cells(R, 3)).Value     ' A:C
            Rm = FindMatch(Entry, Ws, WsName)
            If Rm Then                              ' rm = 0 if not found
                With Ws.Cells(Rm, 5).Resize(1, UBound(Entry, 2))
                    .Value = Entry
                    .Interior.Color = vbYellow
                End With
            End If
        Next R
    End With
    Application.ScreenUpdating = True
End Sub

Private Function FindMatch(Entry As Variant, _
                           Ws As Worksheet, _
                           WsName() As String) As Long
    ' return zero if no match was found

    Dim Rng As Range                        ' search range
    Dim Fnd As Range
    Dim Rl As Long
    Dim i As Long

    For i = 0 To UBound(WsName)
        On Error Resume Next
        Set Ws = Worksheets(WsName(i))
        If Err Then
            MsgBox "Worksheet " & WsName(i) & " doesn 't exist.", _
                   vbInformation, "Missing worksheet"
        Else
            With Ws
                Rl = .Cells(.Rows.Count, 1).End(xlUp).Row
                Set Rng = .Range(.Cells(2, 1), .Cells(Rl, 3))
                Set Fnd = Rng.Find(What:=Entry(1, 1), _
                      After:=Rng.Cells(Rng.Cells.Count), _
                      LookIn:=xlValues, _
                      Lookat:=xlWhole, _
                      SearchOrder:=xlByColumns, _
                      SearchDirection:=xlNext, _
                      MatchCase:=False, _
                      MatchByte:=False)
                If Not Fnd Is Nothing Then
                    FindMatch = Fnd.Row
                    Exit For
                End If
            End With
        End If
    Next i
    If Fnd Is Nothing Then
        MsgBox "Code " & Entry(1, 1) & " wasn't found.", _
               vbInformation, "Missing Code"
    End If
End Function