The theme is love, especially first love. In the stories Asya and First Love, we see through the eyes of an adolescent boy, coming to terms with his feelings about the first women he loves. She may walk and talk and have a name, but she is most of all a woman of his fantasies.
The most affecting story, for me, was Mumu about a deaf and dumb peasant. First he yearns for an unobtainable young woman, then learns to give his love to Mumu, the dog he adopts. Finally he discovers that no love is available to a man in his situation.
Certain people appear again and again in Turgenev stories, for example, a giant of a man whose incoherence is both a cause and a result of his limitations. Gerasim in Mumu and Martin Harlov in King Lear of the Steppes are such men. Also present is the dominating and domineering woman, mistress of her own wealth (so, usually, a widow) who enjoys her power over others. Sometimes she is wicked, a quality she doesn’t recognize in herself. In Mumu,
…she rarely went out and was solitarily living through the final years of avaricious and boring old age. Her own day, cheerless and unpleasant, had long since passed; but the evening of her days was blacker than night.
She may mean well, but meddling often has unforeseen consequences. In King Lear of the Steppes,
My dear mother was very selective in her acquaintances, but she would receive Harlov with particular warmth and was always ready to make allowances for him…. My mother also found him a wife. She married him to a seventeen-year-old orphan who had been brought up in her house.
These fictional women are based on Turgenev’s own wealthy and imperious mother. He can use her character successfully, both the good and bad sides, because his power as a writer is to tell the story. The characters may judge each other — and do — but Turgenev does not. For example, his sympathies are with the peasants, but he still tells us that they are ignorant, given to petty thievery and usually drink too much when it is available.