How was there life of Wang Lung, O-lan and their kids, while they lived in the city.

This question is about the novel The Good Earth by Pearl S. Buck. Wang Lung and O-lan were a young hard-working couple that left the countryside with their kids and Wang Lung's dad to escape famine, drought, flooding, and locust (Otherwise, they would all have died).

In the city, they also lived in harsh conditions, but at least there, they could earn some money to buy food. Wang Lung found a job pulling a rickshaw he rented and O-lan and the kids became beggars. Over time, they learned that they could only make enough money to eat, and nothing more. The couple even thought of selling her daughter so that they could have a bit of money and go back to their home and she could have a better life, but never actually did it, and the boys started to steal until their father discovered them. The family was discouraged but at the moment saw no better option than to keep going on.