"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."
You also missed the fact that they had a valid search warrant.
Are you implying that it's somehow difficult for the police to get a warrant??? They were probably acting on the tip of an "anonymous source" or some other unassailable vestibule of integrity and forthrightness.