I am a Brazilian student. Where do I find "DOG DAYS" and "THE DUNGEON MASTER" by Sam Lipsyte in the Portuguese language?

Sam Lipsyte is an American short story writer and novelist whose work often reflects a dark sense of humor and quick-witted dialogue. His story "The Dungeon Master" can be found in his most recent collection, entitled The Fun Parts, which was published in 2013 by Farrar, Straus and Giroux (although it was originally published in The New Yorker in 2010). As the title of the story may suggest, the narrative follows a group of friends who play Dungeons and Dragons and the fight that ensues between the titular Dungeon Master and the fourteen year-old narrator. Unfortunately, The Fun Parts has only been translated into Italian (as La Parte Divergent), and no Portuguese translations of the book exist. 
"Dog Days," however, is not a short story that was written by Lipsyte; rather, it is authored by Judy Budnitz as part of her 1998 collection Flying Leap. The story follows the dissolution of human civilization that one family faces over the course of a year and the strange arrival of a human dressed in a dog costume on their doorstep. Unfortunately, this collection is also not available in Portuguese, having only been translated from English into German, Dutch, and Japanese. 
Your best bet would, thus, be to talk to your teacher about locating someone fluent in both Portuguese and English who could translate both stories for you since neither are available in the language you desire! Best of luck!