You have a two fold problem, the first is poor training. once habit are established it is difficult to break them. The second is the residual odors from these poor behaviors.
Dogs can be re-trained but it take time and commitment using "positive" reinforcement. rubbing a dogs nose in it and saying NO are training methods that do not work. If your dog responds to treats then you have a distinct advantage. Repeated trips outdoors and rewards for doing their business outside will work...but it takes time.
We have a senior ( 14 year old) wiener dog who has begun to become incontinent. We picked up some medical absorbent pads and have them set up in a dedicated tiled surface in the home. She is using that are now and then. We probably do not have much time left with her as she was diagnosed with pulmonary hypertension and spends a lot of time in an enclosed special kennel with an oxygen concentrator attached. but for now we are trying to make her life a bit more comfortable.
Unfortunately, I don't know of anything you can simply "spray" to stop a dog from using your house as its bathroom. Most likely, some training (or retraining) by you is going to be required to solve your problem. However, more details from you would be helpful. Is this a puppy who needs housebreaking? An older dog that has been housebroken but started having accidents? Do you have an un-neutered male? How old and what breed? (Some breeds, especially some of the small ones, can be more difficult to housebreak. Likewise, it's sometimes difficult to housebreak an older dog you may have just adopted.) Is the dog trained to stay in a crate or does he/she have full run of the house 24/7? What surfaces is he/she urinating on? (There are many homemade recipes and commercial products that will help neutralize the urine odor in carpet and furniture so the dog doesn't repeatedly return to the places he/she has "marked" as the bathroom. My husband is a former police K9 officer and we've had dogs for more than 35 years. Through the years, we've dealt with our share of canine potty issues caused by various things. I'd be glad to try to offer some suggestions but more specific info about the dog and your problem would allow me to zero in on what tips might help you.
@Luann Szymanski you didn't mention how old the dog is or what breed. For the spots that you still have, would recomend you rinse then soak with vinegar followed by baking soda on top - let dry then vacuum - this has worked for us with our pets.
Try to limit the free roam of the house. Babygates work well for this and are easily removed when required. We used one at the bottom of the stairs to prevent the dog from going up when we weren't home.
For training, take the dog outside regularly and as mentioned by KMS mentioned, offer treats when successful. Some people find crating the dogs at night and when they are not home helpful as well. Haven't done that one, but I have heard it is good to control the animal.
Hope this helps and good luck - been there done that LOL Thanks for posting :)
Usually, if it's a male, neutering is the answer. I also kept a spray bottle of water and sprayed a stream at him.. Seemed to give him the idea that was a no-no.