The edition I read is titled "The Undiscovered Chekhov: Thirty-eight New Stories" (hardcover). There is no foreword, only an introduction by the translator, Peter Constantine. This edition is copyrighted 1998, and published by Seven Stories Press. But the stories contained here are the same as those in other editions listing forty-three or forty-one stories.
In his earliest years as a writer, Chekhov wrote as a journalist in that he had to meet deadlines and produce as many stories as possible in order to make some extra income. These stories are short, sometimes more anecdote than story, a vignette or scene or slice of life. But they are vivid, and give a strong impression of the world that seemed chaotic to the young Chekhov. The final stories are absurdist, anticipating trends in fiction by at least twenty years.
Chekhov grew from writing with humor and sometimes silliness into a deeply humanitarian, compassionate and insightful writer. I can see in some of his sketches here the characters he will explore more deeply in his later work, his careful depiction of the arc of a life, and the role of circumstance, or perhaps fate, in guiding a life.