Why did the Nazi party burn books ?
I believe your question is in reference to the 1941 film, The Power and the Glory. This English-language film is based on the story A Man Without a Country, by Noel Monkman, and details the tale of a Czech scientist who tries to escape the power of the Nazi party. He has recently been working on a new type of fuel and accidentally develops a type of nerve gas, which he fears the Nazis will use for evil purposes.
One of the means of social control the Nazi party employed was the burning of books that did not fit into their ideals. Censorship by way of destruction of any "Un-German" books both exerted symbolic control over the type of media people engaged with and served to prevent anyone from reading those texts in future. Book burning and the destruction of works of art were intended to "purify" the intellectual culture of Germany under the Nazi regime. Books by Jewish scholars, or those which contained themes of homosexuality, disability, and communism were burned.
There is also a book by the same title, but it has nothing to do with the Nazi party. The 1940 book The Power and the Glory is about a fictional Catholic priest living and working in Mexico.