Task: Question Answering
Input (English): Passage: One dark stormy night, Injun Joe accepts a job position from Doctor Jonas Robinson. Tom Sawyer is then seen running away from home. He and his friends ride down the Mississippi River on a raft, but hit a sharp rock, which throws Tom into the water. His friends find him washed up on the shore, and Tom finds it was Huck Finn who carried him to safety. Huck learns of an unusual way to remove warts - by taking a dead cat to the graveyard at night. There they witness Injun Joe and Muff Potter, the town drunk, digging up the grave of Vic "One-Eyed" Murrell for Doctor Robinson. A treasure map is discovered and when Doc tries to betray the two men, Injun Joe murders him with Muff's knife.
The next morning, Muff is charged for the murder.  Unfortunately, Tom and Huck had signed an oath saying that if either of them came forward about it, they would drop dead and rot. The boys embark on a search for Injun Joe's treasure map, so they can declare Muff innocent and still keep their oath. The only problem is, the map is in Injun Joe's pocket. After Injun Joe finds the last treasure, he burns the map, leaving no evidence to claim Muff innocent. Joe then discovers that Tom was a witness to the crime. He finds Tom and threatens he will kill him if he ever tells anyone about the murder. However, at the time, the entire community believed that he was dead, and the friendship between Tom and Huck starts to decline because of the fact that their only evidence (the map) to prove Muff innocent, while preserving their oath, is destroyed. 
Question: What are the full names of the characters who search for Injun Joe's treasure map?
Output (English): Tom Sawyer.