You can sync multiple Google calendars with vCita.
In most cases, you will have multiple calendars under a single Google account. But if you have different Google accounts, you will first need to subscribe them all to one account and then sync that account with vCita.
Click here to learn how to add to your Google calendar, calendars from other accounts.
To sync your Google calendar with vCita, visit your Calendar settings page.
Click on Sync Availability button for Google/Android and follow the instructions to complete the synchronization.
Once the synchronization is done, you will have the option to "Select calendars to sync" and you will be able to select from a list which of your Google calendars to sync.