protected override void OnQueryChanged(string oldValue, string newValue)
{
base.OnQueryChanged(oldValue, newValue);
if (string.IsNullOrWhiteSpace(newValue))
{
ItemsSource = null;
}
else
{
ItemsSource = Vaccines
.Where(session => session.Name.ToLower().Contains(newValue.ToLower()))
.ToList();
}
}
