Get only required fields data through API

Summary

Get REST API should fetch only required fields data

Content

Hi,

We are running a REST API to get information related to a transaction line in CPQ.

When we run the following API, it gets all the fields available in system on Transaction Line and from configuration.
METHOD : GET
REQUEST URL : https://****.bigmxxxachines.com/rest/v8/commerceDocuments{ProcessVarName}{MainDocVarName}/(_id}/{subDocVarName}/{subDocNum}/transactionLine
 

But, we want that this API fetch only those fields which we want to get data from.

Is it achievable from the same API? Or please identify if we need to use any other API to fulfill our requirement.