I have a chihuaha mix and I housetrained him within two weeks! I also stay at home so it made it easier but I agree with everyone else, crate training is the only way to go! You should also get a spray like Nature's Miracle to clean the spots that your dog is going at, this should take the smell out so your dog won't be drawn to that same spot over and over again! What I did for my dog is I bought a little bell and hung a bell from the door knob to where he could reach. Every time I took him outside I had him sit and I took his paw and had him ring the bell and I would say "good boy!" and then let him outside. After just a couple of weeks he made the connection to ring the bell when he wanted outside. So now every time he wants outside, whether it's to relieve himself or just to play, he rings the bell, all by his little self! It's so cute. This way he doesn't have to scratch at the door or whine. And now that he knows that he eliminates outside only, I can leave the house for a few hours and he won't go inside, he waits till I come back home.
(Before I got this dog I housetrained my little maltese by getting her a dog litter box, you can maybe do this for your dog since she is a toy breed and since you're not always home. This also requires crate training, only let her out of the crate when you can watch her like a hawk, don't let her have one accident or she'll think it's ok to go whenever she wants! Take her to the box and give her the command to go, if she doesn't go after about 3 minutes, put her back in her crate for about an hour or so and try again. If she goes, then she can stay out and play. And remember that dogs , esp. little ones, need to use the potty after they eat, drink sleep,or play.)
You and your puppy will get the hang of it eventually, you just have to be consistent and try not to let her have any accidents! Good luck!