EBSCO english (Cinahl, ASP, Business Source Complete...): Combine Searches

From Advanced Search, you can choose between AND or OR from the left side of the search bar
In the same search block, you only need to select one of the options. You can always combine your searches from Recent activity.

From Recent activity you can combine multiple search strings.
Select the keywords or search strings you want to combine and click the ‘combine search’ icon and choose whether you want to combine with AND or with OR

You can combine your free text words with the corresponding controlled keywords in the same search string.
Once you have your free text words, you can then search on the controlled keywords and click Add to search.

Once you click Search, you can see your combination of free text words and controlled keywords.

Normally, NOT should be used with caution as you risk excluding relevant results. However, it may be necessary if you need to limit the results.