how to retrieve zoho crm data?

how to retrieve zoho crm data?

i have one statelessform name "search" in which i have username a single line text and one search button.
when i entered a valid username it search the data and display in page(html page).
but i need to add related field data as well. from where i am searching i have one field account name(ZohoCRM) i wnat to fetch account details as well how?