Sending bitcoins to a "Sending address" in Bitcoin Core
In Bitcoin Core, the sending address refers to the address that you have saved as a "contact" in the client. You can save the address with a nickname eg. Coinbase address. 
The receiving address refers to the address which you can use to receive coins. The way Bitcoin works is that a transaction spends the unspent output from the receiving addresses. Hence, it depends on which receiving address you received coins from, your coin control and amount.

E.g. 
1. If you receive 1BTC on 1AddressA and spend 1BTC in the client, the blockexplorer will identify the origin as 1AddressA. 
2. If you receive 0.5BTC and 1 BTC on 1AddressA and 1AddressB respectively and you spend 0.5BTC, the blockexplorer will identify the sending address is 1AddressA. 
3. If the scenario is the same as 2, and you spend 0.6BTC, the sending address will appear as from both and there will be another output going to another address in your client. It is called the change and the address isn't showed within the client. However, you can spend it in your next transaction, I don't know why there's no balance but what I know that the transaction to these addresses shouldn't appear as they are change addresses.

Why are they not on transactions list?

Because Bitcoin core using bip32 
and change addresses transactions have different derive path. 

Example

m / purpose' / coin_type' / account' / change / address_index
Normal addresses path:

m/44'/0'/1'/0/i


Change addresses path:

m/44'/0'/1'/1/i