Public Class frmLookup

    Private _Datasource As List(Of String) = New List(Of String)

    Private Sub frmLookup_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim oTable = GetDatatable(10)


        LookUpEdit1.Properties.DataSource = oTable
        LookupControl31.Properties.Datasource = oTable
    End Sub

    Private Function GetDatatable(Limit As Integer) As DataTable
        Dim oDatatable As New DataTable
        Dim oColumns As New List(Of DataColumn) From {
            New DataColumn("Col1", GetType(String)),
            New DataColumn("Col2", GetType(String))
        }

        oDatatable.Columns.AddRange(oColumns.ToArray)

        For Each Item In _Datasource.Take(Limit)
            Dim oRow = oDatatable.NewRow()
            oRow.Item("Col1") = Item
            oRow.Item("Col2") = Item & "_" & "SomeLong Random(String) !!!111einself"
            oDatatable.Rows.Add(oRow)
        Next

        Return oDatatable
    End Function
End Class