I notice you're looking for "High School Musical 4 online sa prevodom" — which means "with subtitles/translation" in Serbian/Croatian/Bosnian/Montenegrin.
Would you like a summary of the actual High School Musical 3 plot, or help finding legitimate sources with Serbian/Croatian/Bosnian subtitles?
However, it's important to clarify: in the original movie series. There is High School Musical 3: Senior Year (2008), but no official HSM4 with Zac Efron, Vanessa Hudgens, or the original cast.