Federal question cases are civil cases heard when a person who brings a case is going against federal law. It is a law applied in the United States when a plaintiff goes against a treaty in which the US is part of or when the constitution of the United States is been violated.
A search warrant is a court order that a magistrate or judge issues to authorize law enforcement officers to conduct a search of a person, location, or vehicle for evidence of a crime and to confiscate any evidence they find.