How do I create an API request to retrieve only one Invoice Record with Invoice number?

How do I create an API request to retrieve only one Invoice Record with Invoice number?

Hello I am trying to use the API system to simply retrieve one PRE-DETERMINED Invoice number at a time. Along with that request I am including some basic fields.

My problem is when I execute the code below I get a list of records instead of the invoice I am looking. For obvious reasons I have masked the ticket number and apikey. Would it be possible for someone to tell me if I am using the right command e.g. getCVRecords or getRecors WHAT IS THE RECOMMENDED command for and retrieve one record. Please note we ONLY KNOW and can submit on the request below the INVOICE NUMBER and not the INVOICEID.
Please advise
Thank you
Gilbert
 
https://crm.zoho.com/crm/private/xml/Invoices/getRecords?newFormat=2&apikey= *********$&ticket=********************&cvName=API&Invoice Number=209935000001634091&selectColumns=Invoices(INVOICEID,Status,Contact Name,Invoice Number)