may be it has been more that 2 months and your history has been automatically deleted but you can keep it as long as possible using this adon https://addons.mozilla.org/en-US/firefox/addon/expire-history-by-days/ It will expire after the date you set.

How about my bookmarks? My all files,history and bookmarks are all gone i don't know why? It just happened when i open my mozilla after resting an hour.

see

Recover lost or missing Bookmarks

Recovering important data from an old profile

Some only has been restored but my other bookmarks,history and password has not been restored. It's nice your helping my problem sir amitshree. I hope i can contact you personally to see my problem.

see also

Profiles - Where Firefox stores your bookmarks, passwords and other user data 

Back up and restore information in Firefox profiles

if you have been using other browsers also you can import from them too.

Import Bookmarks from Internet Explorer

Import bookmarks from Google Chrome