One option to remove stains is to apply wool detergent directly onto the stains and put the laundry in a bag for 1-2 hours before washing.
Then remove the clothes from the bag and wash in the machine on a wool program with a wool-wash detergent. 

If you have an intractable stain, you can try to apply some extra wool detergent to the machine. However, stains of powerful colors can be difficult to remove completely from wool in pale colors.
Here you can see our instructions for the correct washing of your wool products from DILLING: How do I wash my wool?

At DILLING we have our very own perfume-free wool detergent, which we warmly recommend. We have chosen this detergent, because it is gentle to the wool and has a very good washing ability against stains and dirt. 

You can read more here: Dilling Wool Detergent