Three of these are rewarded for completing the quest "Elder Charms of Good Forturn" which is gotten from Eldar Lin who stands below the portico of the Shrine of Seven Stars in the Vale of Eternal Blossoms. To complete the quest you must have 90 Lesser Charms of Good Fortune. As of 5.2 this quest is no longer available. Instead these are now drops from the MOBs on Thunder Isle.