Dachshunds can be notoriously difficult to house train. Many tools can be useful in house training, we recommend crate training for this, as well as general usefulness. Dogs pick up on house-training much faster if crates are utilised.
Dogs will not potty where they eat or sleep, so it is natural for them not to go in their crate. If taken outside immediately on being released from their crate they quickly learn to associate “outside” as the place to go. Another useful tool for dachshunds are pet doors.
Whether allowing them access all day while you are gone or only when you are home, a pet door allows them to head outside on their own when the feel the need and avoid the risk of their human missing the signs they might give. Reward training when they go potty outside is also a tip. If you offer them lots of praise for going outside they will be more apt to learn.
Doing this can also allow you to teach them to associate a specific word with going potty which can be very helpful on road trips, apartment life or any time you need them to get on with it, such as standing in the rain with them holding an umbrella when they refuse to go out otherwise!