Sırpça zor bir dilmi öğrenmesi?

I understand every word,but I don´t see a point of this sentence?
Is Serbian a difficult language his learning?
But,my try would be:
Is it hard to learn Serbian?

Your translation is correct. But the Turkish sentence is not in the correct order. It should be like this: "Türkçe öğrenmesi zor bir dil mi?"

Thank you.
I think that the one who sent me that message is Turk..Yes,I checked it,he lives in Istanbul..
But I don´t get it,why there is öğrenmesi ?
Sırpça öğrenmek zor mudur? - Is that correct? 

Let me tranlate it literaly:

Turkish is a language whose learning is difficult.

Öğrenmesi is "whose learning" in the sentence.

Hm,I think I understand it now more.
But not tottaly...
It´s like: Is it learning Turkish hard language?  ?
 

yes.

tunci hocam şu topiğe bir el atsan

Is Turkish a hard language to learn? 

This is better.

Abla Hoca and Henry Hoca are good in explaning this subject, but I ll try ;

Türkçe öğrenmesi zor bir dil mi?" 

öğrenmesi --> if we break it down , we see the possesive construction.

öğrenme [learning] + s + i ---> its learning 

so literally ; is Turkish a language that its learning is difficult ?

in other words ;

Is Turkish is a language that is difficult to learn ?

But you are the best.

Çok sağ ol,tunci! Nihayet anladım.  Çok şükür.

Abartma  Nemanja . Neyse, anladığına sevindim. Rica ederim.