Querying specific parameter

Problem: Querying specific parameter

Expected outcome: parameters value only

Foreman and Proxy versions: 1.20

Other relevant data:
searching for kernel in facts api:
/api/hosts/594/facts?per_page=1000&search=kernel

But I get all parameters starting

kernelmajversion "4.15"
kernelversion "4.15.0"
kernelrelease "4.15.0-46-generic"
kernel "Linux"

But I want only the last one.