static void Main(string[] args)
{
var sd1 = SearchDescriptor <Person> .Create(p => p.Firstname, Operand.Equal, "Иван");
sd1.OpenBrasket();
sd1.Or(p => p.Firstname, Operand.NotIncludes, "0");
sd1.Or(p => p.Birthday, Operand.Equal, new DateTime(2051, 01, 12));
sd1 = sd1.And(p => p.Firstname, Operand.Equal, "ewkfg");
sd1.CloseBrasket();
Console.WriteLine(sd1.ToString());
Console.WriteLine();
Console.WriteLine(Persons.AsQueryable().Where(sd1.ToExpression()).Count());
Console.ReadKey();
}
