The encrypted/masked amounts are stored in the tx ecdhInfo field.
If you want to view these masked amounts on an explorer:
Scroll to the bottom and click "Show JSON representation of tx".
If you want to view in a daemon:
You will need the address/subaddress and private view key to decode the amounts.
Go to xmrchain.net and fill in the missing address and viewkey.
Edit: Here's some light reading for deeper knowledge of Monero.
Transaction structure is described in detail in Appendix A/B.