"Raking light" is critical to seeing all the details in relief carving. The kind of flat even light produced by overhead lighting in most workshops actually hides both the 3 dimensional features of carving and any flaws.
John Bivins, who was one of the most talented carvers of the late 20th century, actually had his bench set up so he could effectively turn off the overhead light by tilting the bank of hanging fluorescent tubes away. He then used a high watt bulb in an articulated arm light to bring harsh, sharp light on the carving at a very low angle--- 10 to 30 degrees.
Ever since I saw that set up about 1970, I've used variations of it.
Another tip is to take the stock out into bright sunlight.
Gary