A more thorough explanation:

vulgo quaesiti

Vulgo quaesiti is a Latin term used to describe children who are born out of promiscuity, making it impossible to determine their true fathers.

One example of vulgo quaesiti is a child born to a woman who had multiple sexual partners around the time of conception. Another example is a child born to a prostitute who had many clients during her pregnancy.

These examples illustrate the definition of vulgo quaesiti because in both cases, the true father of the child is unknown due to the mother's promiscuity. The term is used to describe children who are born in these circumstances.