No. If you are using multiple vaults, then each vault need to be synchronized with a separate cloud account. Although, by different cloud, we mean different accounts, not services i.e. you can have multiple accounts on Dropbox and set up sync of different vaults with them.
But in case, if you are using the WebDAV/OwnCloud or Folder sync, then you can use the same cloud to sync different vaults by defining a separate path/folder for each vault.