In your case, it is almost impossible. Don't lose heart, there are other ways. Is to directly search for topics. For example, the first unit of the first volume of the eighth grade of your textbook is parallel lines, and there is a section about the nature of parallel lines. You can directly search for topics. In Baidu video, after all, junior high school students have learned these things, and there are any versions.
I hope my answer is useful to you.
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