public class EmployeesViewModel : ViewModelBase
{
    // private IUnityContainer Container; // УГ detected!

   private Func<Owned<IDataContext>> _contextFactory;

    public EmployeesViewModel(Func<Owned<IDataContext>> contextFactory)  // OK
      //(IUnityContainer container) // УГ detected!
    {
        // Container = container; // УГ detected!
        _contextFactory = contextFactory; 
    }

    public override void Load()
    {
        base.Load();
        Find();
    }

    public void Find()
    {
        var items = Enumerable.Empty<Employee>();

        if (!string.IsNullOrEmpty(LastName))
        {
            using (var ctx = _contextFactory())
            {
               items = ctx.Value.GetEmployees().Where(d => d.LastName.Contains(LastName));
            }
        }

        Employees = new ObservableCollection<Employee>(items);
        TotalRows = Employees.Count;        
    }
}