Hi,
Thank you for the details, I can confirm, this is an issue with the term search when polylang is active. I was able to replicate the problem on my test servers, as well as correct it. It requires changing one of the plugin files though.
I have tried to connect via FTP, but it does not seem to work. Can you please check if the URL is correct, and let me know if there is any special configuration I need (port etc..)? Thank you!
If you prefer to make the fix yourself, then just follow these steps:
1. Make sure to back-up your files, just in case
2. Open up the wp-content/plugins/ajax-search-pro/includes/classes/search/class-asp-search-terms.php file on your server
3. Change it’s contents to this.
4. Save the file
After this change, it should start working correctly.