Which Sufi Saint's tomb is enshrined in the Ajmer Sharief Dargah? What was his main belief?

Ajmer Sharief is the holy shrine of the sufi saint, Khwajah Moinuddin Chishti.

The main beliefs of Khwaja Moinuddin Chishti were achieving oneness with God, devotion to the Divine, leading a pure life, showing compassion and charity for the helpless and poor.