Splynx Api Search customer with mail

I am start using the splynx api for a customer.
Customer want to create a mobile app and search fthrough api for a customer if exist with mail.
i am using postman and test in the splynx demo but can make it work.
Any help appreciated.
Just for information api keys,secret etc working in other requests.
just with this request i don’t get a single pesron, but a list of all customers.
here is a simple example.
http://demo.splynx.com/api/2.0/admin/customers/customer?{"main_attributes": ["login": "", "name": ""], "additional_attributes": ["email": ["clark.willis@ispframework.com"]}

i have figure out !!

Can you share your solution? I am having a similiar issue