Many editions of the book (like the 1983 or 1987 versions) actually include solutions and detailed hints at the back, which acts as the official GDZ.
Look for the book on platforms like Labirint or Ozon where teachers often share digital keys in the reviews or forums. gdz po fizike 10-11 klass bakanina belonuchkin kozel
If you're stuck on a problem from this book, the "secret story" to solving it is often to and identify which fundamental law (like Conservation of Energy or Momentum) is being challenged. These problems are designed to be "fun to solve" once you find the hidden clue in the text. Many editions of the book (like the 1983