Travel notes with thoughts and historical digressions

It is an old truth: if you can't find something, you should look somewhere else.  It is the prose of life: it is useless to look for your keys in your purse, if you have left them at home by the mirror, and it is useless to look for your cell phone in your pocket if you have left it in the store. And it is totally  useless to search for Genghis Khan's tomb where it is not. But where should you search?