Serbia thinks this way because of the friendly relations between the two countries, which is what Serbian President Aleksandar Vui said at the press conference. Putin rescued Serbia from the nameless genocide accused by western countries in 20 12, which was like a savior for Serbia. It avoids blaming the civil war entirely on the Serbs and maintains Serbia's international image. In the eyes of Serbs, Putin is a hero of justice.
Putin also stood firm at the ceremony of NATO bombing Yugoslavia in 1999 and always supported Serbia. The history and culture of the two countries are closely linked, and Putin has even repeatedly expressed his support for Serbia's sovereignty and territorial integrity. In 2008, the United Nations resolution declared Kosovo's independence invalid, including Russia and Serbia, whose positions were exactly the same.
This firm stance is in stark contrast to Yeltsin's presidency. When Yeltsin was president of Russia, he only made some verbal condemnation of NATO countries, and his position was not firm. In contrast, Serbs love and respect Putin more.