Organisation de procédure (recherche)

option explicit
Sub cherchepartout(quoi As String)
Dim wb As Workbook
If Not cherchedansunfichier(ThisWorkbook, quoi) Then
    Set wb = Workbooks.Open("Documents/Archives.xlsx", , True)
    If Not cherchedansunfichier(wb, quoi) Then
        'rien trouvé
    End If
    wb.Close
End If
End Sub
Private Function cherchedansunfichier(wb As Workbook, Var As String) As Boolean
Dim sh As Worksheet, lig As Range
For Each sh In wb.Sheets
    For Each lig In sh.Rows
        If lig.Cells(1, 2).Value Like "*" & Var Then
            'trouvé
            cherchedansunfichier = True
            Exit Function
        End If
    Next lig
Next sh
cherchedansunfichier = False
End Function

Private Function cherchedansunfichier(wb As Workbook, Var As String) As Boolean
Dim sh As Worksheet, lig As Range
For Each sh In wb.Sheets
    If Application.CountIf(sh.Columns("B"), "*" & Var) = 1 Then
        Set lig = sh.Columns("B").Find(what:=Var, LookIn:=xlValues).EntireRow
        'trouvé
        MsgBox lig.Cells(1, 2).Value
        cherchedansunfichier = True
        Exit Function
    End If
Next sh
cherchedansunfichier = False
End Function