showing in google

simple question, in brief Why google shows When I input my site url? What Does this mean to the website? How to avoid, remove or improve it? Any friend have the same question here? :beach_pla

Few days back when i checked my site on keyword which i usually check it was not showing in search engine my site is not showing on even keywords i dont know what happaned my organic traffic goes down is it goole dance or my site is sand boxed how can i get from this situation plz help