Share your experience!
I updated my xperia z1 compact to last version (4.4.4). Google updated google search with "ok google" voice command in my language (Spanish), and is not working. I have a tablet, and other phones, but only on my xperia z1 compact dont work. There is a problem with this on z1 compact?
Can you please elaborate. When you say its not working, what do you exactly mean? Like is it not recognizing the words or its not performing the appropriate action or what?
I open google search app (Google Now), and it visualize search bar and microphone icon. In this screen you can say "ok google" and it launch search voice or voice commands to do tasks like add event calendar, set alarm, etc...
But in xperia Z1 compact with android 4.4.4 it didn't work. I open google search, say "ok google" and its not recognized. Ok google its working good on all devices i can probe it, but don't work con z1 compact.
That is odd. becuase on my Z1C with Android 4.4.4 it's working perfectly.
You can try uninstalling and reinstalling Google Now. But I am not sure if that will solve your problem.
i try to uninstall and install again yesterday, but the problem persist, and i don't see the problem in any forum, it's why i'm worried, any one else have the same problem... 
Are you sure you enabled google search?Is your connection working fine?
If you tap longer on home,rise to google now,tap on the 3 buttons and select settings,do you have google now switched to on?