where do i get 15 more stars i need 15 more only and i have done these stars quest ?

Grandparent and Grandchild who are robbed Pig's Nightmare Story of the Hood Girl Sheep's Nightmare The Mark of Going Home The dodge ball of Hawaii Mysterious Icy Cave Match Girl Protector of the Holy Spirit Xaolan's Fate The Piper's snake flute Unbelievers fish Food Beautiful Immortal Fox Houyi Incident Who's the better hunter? Question and Answer Worry in the hart Pray to the God Frog Prince Mayan Door Ball Competition Mayan Tribe is Raided
Don't Leave! Shasha!Treasure Box of Water Monster Magellan is in danger!Mao and Xao Mo