NSMutableString and (character)-encoding issue: getting \U00fc in case of ü

i am fetching my entity from coreData and saving the result of fetchrequest to an NSMutableString for text to speech.

self.ttsInboxCards = [[NSMutableString alloc] initWithString:@""];  
 [self.ttsInboxCards appendString:[[entitySetsCards valueForKey:@"cardTitle"] description]];
 

And in NSLog i am getting this values:

F\U00fcr | schl\U00e4ge | zuh\U00f6ren  
 

which should be:

Für | schläge | zuhören  
 

I have tried a lot of things to get the correct encoding, for example with:

stringWithUTF8String:  
 

and so on, but nothing worked.

How can i prevent this issue?

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