My own solution was created a method like the next one:
-(void)setColorForText:(NSString*) textToFind originalText:(NSString *)originalString withColor:(UIColor*)color andLabel:(UILabel *)label{
NSMutableAttributedString *attString = [[NSMutableAttributedString alloc] initWithString:originalString];
NSRange range = [originalString rangeOfString:textToFind];
[attString addAttribute:NSForegroundColorAttributeName value:color range:range];
label.attributedText = attString;
if (range.location != NSNotFound) {
[attString addAttribute:NSForegroundColorAttributeName value:color range:range];
}
label.attributedText = attString; }
It worked with just one different color in the same text but you can adapt it easily to more colores in the same sentence.