The main theme could be about redemption. Often in such novels, characters strive to overcome their past mistakes and find a new path in life, seeking forgiveness and self - improvement.
In a 'Tender Mercies' type of novel, there could be a character who is a bit of an outcast. This person may be dealing with some internal struggles. And then there could be characters that represent different aspects of society. For example, there could be a judgmental character who challenges the main character's growth, and a kind - hearted character who offers the tender mercies that are central to the story.
Since I haven't read 'Small Mercies: A Novel', it's hard to say exactly. However, it could be a story that delves into the lives of ordinary people. It might explore themes such as love, loss, and redemption. The'small mercies' in the title could be those little moments of grace or kindness that the characters encounter during difficult times. For example, a character might be going through a tough financial situation, and a small mercy could be a neighbor offering some food or help without being asked. This could then lead to a transformation in the character's perspective or relationships.
Since I don't know the author of 'Small Mercies, A Novel', I can't give you the exact other books. But generally, you can search for the book on Amazon. Once you find the book page, it often has a section showing other books by the same author. Another option is to ask at your local bookstore. The staff there are usually knowledgeable about different authors' works.