There are two ways to do this. One is to select Edit from your search history, then check Exclude MEDLINE records, followed by Save. This will edit the set in your search history.
The other is to use the Refine Results on the left side. Under Limit To, select Show More. Next, check Exclude MEDLINE records, followed by Save. This will create a new search set. Good for when you want to go back to the previous set.
Want more search tips and information about CINAHL? Click here.