bubble tea vs pearl tapioca

bubble tea

noun
  • Sweetened tea with milk and tapioca pearls, often including fruit juice, syrup and other ingredients. 

pearl tapioca

noun
  • Small edible balls made primarily from tapioca starch; used in bubble tea. 

How often have the words bubble tea and pearl tapioca occurred in a corpus of books? (source: Google Ngram Viewer )