Book: The gospel according to Artyom

I stir with a long stick long-extinguished coals, lift the pieces of iron. I think I've already screened all of this godforsaken field, and so nothing was discovered, just went to work the second time. And then the third.
What I'm looking for?
Green sprout? Or at least a bone of another creature that wanted me - a lone boy to take to adopt? Or the shadow of the trees that grew there on the day when my mom took me to walk to the Botanical garden? Forgiveness? Hope?
Soot and coals. Coal and soot.