Bharata is a country where many invasion took place: Alexander, Chengiz Khan, Mohammed Bin Qasim, Timur, Nadir Shah, Ahmed Shah Abdali, and British etc.
And, many of them tried to destroyed our thriving heritage including precious scriptures. It is said that British maligned many scriptures with intention of ruining our spiritual culture (which they succeeded). Also, they took away many scripts, scrolls etc. with them and they are kept in the various museums across United Kingdoms.
From time to time, different forms of Shiva and Vishnu imparted knowledge in different forms and domains to different sages, rishis, brahmins, rashtriyas etc. for well-being of humanity. And, I suppose when storing of scripts in the form of written knowledge was practiced, we wrote it down all the acquired knowledge and pass it down as inheritance for new generations to come.
So, currently, if not original, do we have all texts or knowledge in good condition and without tempering with us or we have knowledge gap?
I am looking for authentic answer.