How to send the coins from the right wallet address.
Let's have a look at the Change article of the Bitcoin wiki: "When the output of a transaction is used as the input of another transaction, it must be spent in its entirety. Sometimes the coin value of the output is higher than what the user wishes to pay. In this case, the client generates a new Bitcoin address, and sends the difference back to this address. This is known as change."
Most of the cryptocurrency wallets have been forked from the Bitcoin wallet so they operate exactly the same. When you send a transaction the change goes to the new generated address (unless you specify the output address to be the change address as well). It could easily appear that you have some coins on your wallet but they are spread between different addresses.
In terms of blockchain these addresses are completely unrelated. They just appear in your wallet and the total balance is summed. Usually it is not possible to specify the address from which the funds are sent. However there is a tip how you could select the output address. Before sending your transaction, send all the coins to your own address which is desired to be the output address for the future transcation. This way you will be sure that the funding transaction is coming from a single address and you are sure which one.