You're looking for a good piece about the book "Metro 2033" by Dmitry Glukhovsky, specifically in Serbian (Srpski) language, and preferably in PDF format.
Here's some information:
"Metro 2033" is a post-apocalyptic novel written by Dmitry Glukhovsky, a Russian author. The book is set in a post-nuclear Moscow, where survivors live in the metro tunnels and stations. The story follows the journey of Artyom, a young man who embarks on a quest to save his home and the future of humanity.
The book has been translated into Serbian (Srpski) and is available under the title "Metro 2033" (you can find it as "Метро 2033" in Cyrillic).