To check the ranking of the nanny series, you can search for the novels on various online reading platforms and check the ranking data of the relevant websites. Some common online reading platforms included Qidian Chinese Network, Xiaoxiang Academy, Zongheng Chinese Network, etc. On these platforms, one could search for the title of the series or search by keywords to see the ranking of the relevant novels to find out which of the most popular series were. He could also check the rankings of the milk dad series on other reading platforms to obtain more comprehensive information.