There are few possibility why JSON data not being displayed properly.
To debug your data, use
print_r($your_data);die();
If print_r shows empty or nothing, use
var_dump($your_data);die();
Output:
string '{"en":"Home","fr":"Office","cn":"bar"}' (length=1
Possibility 1) – json data being encoded to html code. Some CMS will encoded the json data output.
To solve this html entity issue, decode the data like example below:
json_decode(html_entity_decode($your_data);
What do you think?