what does siddhartha mean when he refers to the "path of paths" that nust be found? why is he so certain the brahmins nor the samans have found it?

Siddhartha felt there are different paths to take but many of those paths involve desire. He felt that paths, like Brahmin desire to be above others, only lead to Samsara and the endless cycle of birth, life and death. A person's path must be free from desire.