Of course these things aren't written in the bible. Why would they be?
However they are written in old Tibetan books. They are also carved in stone in India, and recorded in Japan.
Further, if you study these old books, then you will see many similarities between them and how Jesus spoke. It is like watching swordsman in the age of the samurai. You knew who taught them by so many tell tale signs. Or, you could just be ignorant and think they all just swing their swords about until one dies.