الاول يجب عمل Row Sours من خصائص vba

ثانية
Private Sub ComboBox2_Change()
Dim i As Long
For i = 1 To Application.WorksheetFunction.CountA(Sheet1.Range("c:c"))
If LCase(Left(Sheet1.Cells(i, 1), 1)) = Me.ComboBox2 And Me.ComboBox2 <> "" Then
Me.ComboBox2.AddItem Sheet1.Cells(i, 1)
End If
Next i
Me.ComboBox2.DropDown
End Sub


أو

اذا كان اسم شيت مكتبوب باللغة العربية
نسمي عامود يحتوي على خلاياء ب اسم معين مثل weet بدل من شيت عربي

'بحث في كمبوبوكس
Private Sub ComboBox2_Change()
Dim i As Long
For i = 1 To Application.WorksheetFunction.CountA(weet)
If LCase(Left(Cells(i, 1), 1)) = Me.ComboBox2 And Me.ComboBox2 <> "" Then
Me.ComboBox2.AddItem weet.Cells(i, 1)
End If
Next i
Me.ComboBox2.DropDown


او


Private Sub ComboBox1_Change()
Dim i As Long
For i = 1 To Application.WorksheetFunction.CountA(Range("a:a"))
If LCase(Left(Cells(i, 1), 1)) = Me.ComboBox1 And Me.ComboBox1 <> "" Then
Me.ComboBox1.AddItem Sheet1.Cells(i, 1)
End If
Next i
Me.ComboBox1.DropDown
TextBox1.Text = ComboBox1.Value
End Sub










End Sub