Hi Alameiras,
In order to make search filter has map like demo, you must use template K2 Directory. But in your folder K2 of JA Directory (templates/ja_directory/html/com_k2) you have copied the wrong structure for ‘ja_k2filter’ folder, just copy only folder ja_k2filter to com_k2, not whole folder ‘templates/ja_k2filter’.
The right structure should be:
com_k2
| default
| directory
| __ ja_k2filter
Then go to K2 category, set template to Directory. And go to JA K2 Filter >> Option >> tab Search Result Item Layout >> Select template to Directory.
You can send me your FTP account, then I can help you set up this.