Try something like this:

Sub SendemailAll()
Dim xOutlookObj As Object
Dim xEmailObj As Object
Dim tempFile As String
Dim strbodymsg As String
Dim wb As Workbook
Dim strbody As String
Dim tempFiles()
Dim DisplayEmail As String, Signature As String
Dim a, b, c, d As String

With Application
.ScreenUpdating = False
.DisplayAlerts = False
End With

ReDim tempFiles(1 To ThisWorkbook.Worksheets.Count)
Dim ws As Worksheet
For Each ws In ThisWorkbook.Worksheets
ws.Copy
With ActiveWorkbook
Dim counter As Long
.SaveAs ThisWorkbook.Path & Application.PathSeparator & ws.Name, FileFormat:=51
counter = counter + 1
tempFiles(counter) = .FullName
.Close savechanges:=False
End With
Next ws

'Create Outlook email=============
Set xOutlookObj = CreateObject("Outlook.Application")
Set xEmailObj = xOutlookObj.CreateItem(0)
With xEmailObj
.Display
End With
Signature = xEmailObj.Body
On Error Resume Next

With xEmailObj
a = ThisWorkbook.Sheets("Sheet1").Range("R1").Value
b = ThisWorkbook.Sheets("Sheet1").Range("R2").Value
c = ThisWorkbook.Sheets("Sheet1").Range("R3").Value
d = ThisWorkbook.Sheets("Sheet1").Range("R4").Value

.Display
.to = a
.CC = b
.Subject = c
Dim n As Long
For n = LBound(tempFiles) To UBound(tempFiles)

.Attachments.Add tempFiles(n)
Kill tempFiles(n)
Next n
'previously saved workbook with single sheet
.Body = d & Signature
If DisplayEmail = False Then
'.Display
'.Send
End If
End With

With Application
.DisplayAlerts = True
.ScreenUpdating = True
End With
Set xEmailObj = Nothing
Set xOutlookObj = Nothing
End Sub

Thanks for answer, but seams when program copying sheets with ws copy it show error "failed".

Are there any hidden sheets in the workbook?

Yes, there were hidden files, I added some in the code.
Thank you very much for your help

Sub Sendemail()
Dim xOutlookObj As Object
Dim xEmailObj As Object
Dim tempFile As String
Dim strbodymsg As String
Dim wb As Workbook
Dim strbody As String
Dim tempFiles()
Dim DisplayEmail As String, Signature As String
Dim a, b, c, d As String

With Application
.ScreenUpdating = False
.DisplayAlerts = False
End With

ReDim tempFiles(1 To ThisWorkbook.Worksheets.Count)
Dim ws As Worksheet
For Each ws In ThisWorkbook.Worksheets
If ws.Visible = xlSheetVisible Then

'ws.Select
ws.Copy

With ActiveWorkbook
Dim counter As Long
.SaveAs ThisWorkbook.Path & Application.PathSeparator & ws.Name, FileFormat:=51
counter = counter + 1
tempFiles(counter) = .FullName
.Close SaveChanges:=False
End With
End If
Next ws

Just to note: cross posted in a couple of places:

https://www.mrexcel.com/board/threads/how-to-send-all-sheets-from-the-same-workbook-separately-in-one-email.1227035/
https://forum.ozgrid.com/forum/index.php?thread/1233082-how-to-send-all-sheets-from-the-same-workbook-separately-in-one-email/