Based on the title "Savchenko Physics," you are most likely referring to the well-known physics problem book (often simply called "Savchenko") widely used in Russia and post-Soviet countries for specialized physics schools and Olympiad preparation.
The full citation for the work usually looks like this: O. Ya. Savchenko, "Problems in Physics" (Задачи по физике), often co-authored with N. N. Ivlev and V. P. Ostroumov. savchenko physics pdf
Here is a report on the Savchenko Physics PDF, detailing its nature, content, pedagogical value, and availability. Based on the title "Savchenko Physics," you are
In many editions, Savchenko marks problems with asterisks: PART 5
Start with no-star problems. Only attempt two-star problems after a month of practice.