Fill ComboBox based on Seach Criteria

One the best approch for this requirement is to add one textbox as search bar which provides the same result you reuired.

Here we need to focus on three things. I'm cosidering that your combobox is in the userform1
and your students data list is in the sheet1.

Now,

There are two events you need configure to perform this task.

1. UserForm_Initialize
2. TextBox1_Change

and the one sub procedure which will populate the result based on the keyword in the textbox

3. Populate_Combobox

Now

Coding for the 1 & 2 is the same

Private Sub TextBox1_Change()
Populate_Combobox
End Sub

Private Sub UserForm_Initialize()
Populate_Combobox
End Sub

Now let's see the code for the Sub Procedure

Private Sub Populate_Combobox()
Dim I As Long
I = 2
Dim LenofStr As Long
LenofStr = 0
With UserForm1
.ComboBox1.Clear
If .TextBox1.Value = vbNullString Then
Do Until Sheet1.Cells(I, 1).Value = Empty
.ComboBox1.AddItem Sheet1.Cells(I, 1).Value
I = I + 1
Loop
Else
LenofStr = VBA.Len(.TextBox1.Value)
Do Until Sheet1.Cells(I, 1).Value = Empty
If VBA.Left(VBA.UCase(Sheet1.Cells(I, 1).Value), LenofStr) = VBA.UCase(.TextBox1.Value) Then
.ComboBox1.AddItem Sheet1.Cells(I, 1).Value
End If
I = I + 1
Loop
End If
End With
End Sub

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