And there are material that they perform that I cannot find in any book or any other source(internet)
With a solid understanding of the fundamentals (by reading the books and resources outlined in your other thread), you most likely will be able to come up with methods for that material. Obtaining the level of understanding will take several years. Many of effects you see might be published by the authors or they might just keep them to themselves because it is their performance material.
One of the things that I've always told my son is that there is no such thing as teaching, only learning. A teacher can be the best there is and there will be no learning unless the student is willing to put the work and effort into it. Similarly, a student who is unwilling to put the work and effort into learning will not learn no matter how good the teacher. You seem to be looking for an easy way to learn everything about mentalism. So let me tell you a secret... there is no easy way.
There are DVDs (Osterland's come to mind) on mentalism, but those have a cost. There have been a lot of free lectures during COVID but those are through a variety of magic groups that you need to be a member of. Also, to be honest, a lot of those lectures haven't been that great and I suspect they will not provide you with what you are looking for.
Rather than seeking methods to effects you see, approach things from a different direction. Find effects in books that you like and perform them. Reading the books ultimately will give you a broad understanding and eventually get you to your goal... but in the meantime you will be able to perform effects that you like.