The particle "Hani "

This particle in modern Turkish  is used as " where, what happened ?, " you know, you said / you promised that [ said to someone who breaks his promise ]

In old Turkish it was "kanı " which didn´t break vowel harmony.

- Hani benim hediyem ?  ---> Where is my present ?   [ Where ]

- Hani dün akşam gelecektin ?  ---> You said you were coming last night. [ But you didn´t , you didn´t keep your word ]

-  Hani o elektrikle çalışan arabalar var ya. ---> You know,  there are cars that run with electricty.[ You know ]

Sometimes , we use it  to say " do you remember " ? 

- Hani  2 sene önce seninle bu kafede buluşup beraber kahve içmiştik ? ---> Do you remember ,2 years ago  we had met in this cafe and had coffee together  ?

hani always seems to refer to a piece of information the speaker and the listener share but sure it is difficult for a learner to use it correctly. Thanks for the enlightening examples.