Option Explicit

Function Saberi(Rng As Range)
Dim Sit As Worksheet
Dim ImeSita As String, ImeCelije As String
Dim Poz As Integer, Sifra As Integer
Dim Red As Range
Dim Vrijednost As Integer
Dim AktivniRed As Integer

AktivniRed = ActiveCell.Row
Const siti = "JanuaryFebruaryMarchAprilMayJuneJuly AugustSeptemberOctoberNovemberDecemberJanuary"
Set Red = ActiveSheet.Cells(AktivniRed, 1)
Sifra = Red
    For Each Sit In Worksheets
    ImeSita = Sit.Name
    Poz = InStr(1, siti, ImeSita, vbBinaryCompare)
    If Poz > 0 Then
    Vrijednost = Vrijednost + Nadji_Vrijednost(ImeSita, Rng, Sifra)
    End If
    Next Sit
    Saberi = Vrijednost
End Function


Function Nadji_Vrijednost(ImeS As String, Rn As Range, Sifra As Integer) As Integer
Dim Sit As Worksheet
Dim Red As Range, RedB As Integer
Dim CEL As Range, R As Range
Dim a

a = Rn.Address
Set Sit = Worksheets(ImeS)
Sit.Activate
Set R = Sit.Range(a)
For Each Red In R.Rows
If Red = Sifra Then
RedB = Red.Cells.Row
Set CEL = Sit.Cells(RedB, 34)
Nadji_Vrijednost = CEL.Cells
End If
Next Red
End Function