Sub poisk_v()
Dim poisk
Dim sFolder As String, sFiles As String
Dim wB As Workbook, wFromB As Workbook
Application.ScreenUpdating = False
Set wB = ActiveWorkbook
  sFolder = wB.Path & "\"
  With wB.Sheets(1)
For x = 1 To .Cells(Rows.Count, 1).End(xlUp).Row
    poisk = .Cells(x, 1).Value
      sFiles = Dir(sFolder & "*.xls*")
        Do While sFiles <> ""
            If sFiles = wB.Name Then GoTo lop
            Set wFromB = Workbooks.Open(sFolder & sFiles)
            For Each cl In wFromB.Sheets(1).UsedRange.Cells
                If cl.Value = poisk Then
                .Cells(x, 2).Value = sFiles
                wFromB.Close False
                Exit Do
                End If
            Next
        wFromB.Close False
lop:
        sFiles = Dir
    Loop
Next x
End With
Application.ScreenUpdating = True
End Sub

For Each cl In wFromB.Sheets(1).UsedRange.Cells
                If cl.Value = poisk Then
                .Cells(x, 2).Value = sFiles
                wFromB.Close False
                Exit Do
                End If
            Next

Sub poisk_v()
    Dim poisk
    Dim sFolder As String, sFiles As String
    Dim wB As Workbook, wFromB As Workbook
    Application.ScreenUpdating = False
    Application.EnableEvents = False
    
    Set wB = ActiveWorkbook
    sFolder = wB.Path & "\"
    sFiles = Dir(sFolder & "*.xls*")
    Do While sFiles <> ""
        If sFiles = wB.Name Then GoTo lop
        Set wFromB = Workbooks.Open(sFolder & sFiles)
        With wB.Sheets(1)
            For Each WhatFind In .Cells(1, 1).Resize(.Cells(Rows.Count, 1).End(xlUp).Row, 1)
                If IsEmpty(WhatFind.Offset(, 1).Value) Then
                    For Each MySheet In wFromB.Sheets
                        Set result = MySheet.Range("A:D").Find(What:=WhatFind.Value, LookIn:=xlValues, LookAt:= _
                            xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, MatchCase:=False _
                        , SearchFormat:=False)
                        If Not result Is Nothing Then
                        WhatFind.Offset(, 1).Value = sFiles
                            wFromB.Close False
                            GoTo lop
                        End If
                    Next
                End If
             Next
        End With
        wFromB.Close False
lop:
        sFiles = Dir
    Loop
    Application.EnableEvents = True
    Application.ScreenUpdating = True
End Sub