Purport

Bhagvan Shri Krishna reveals other manifestations, Kamdhenu the cow in Devaloka, Kandarpa, the deity of love, The great dragon or serpent Vasuki and the thunder.

Kamdhenu the cow in deva Loka is considered as one of the manifestations of Bhavan Shri Vishnu(Shri Krishna). All the cows on this earth the descendant of Kamdhenu. This is one of the main reasons why the cow is the revered animal in Santan Dharma.

Vasuki the king of all serpents. The seat for Bhagvan Shri Vishnu, Sheshnag is his brother. As per the legends, two daughters of Daksha Prajapati married to sage Kashyapa, Kadru then wished to have serpents as her sons. She Got 100 of such serpents. Vasuki is the chief and became the king of all serpents. Sheshnag, Takshaka, and Kaliya are his brothers.

Vajra, the thunder is a weapon of Indra. On earth, we know thunder is generated when charged particles in clouds create high voltage(over 100000) difference from the earth. The high voltage difference breaks down the insulating layer of air. But Vajra the weapon of Indra is a tool where thunder is generated on will.

The deity of love Kandarpa or Kamdeva is one of the manifestations of Lord Shri Vishnu(Shri Krishna)