amulet vs voodoo doll

amulet

noun
  • A kind of protective charm or ornament, often bearing magical symbols, worn for protection against ill will, negative influences, or evil spirits. 

voodoo doll

noun
  • A poppet; a doll made to resemble a person in order to cast spells on them or to galvanize some change in them by modifying the doll, often by inserting pins and needles or by binding it. 

How often have the words amulet and voodoo doll occurred in a corpus of books? (source: Google Ngram Viewer )