The keywords you see, after you perform a search, are highly relevant keywords that are the result of expanding your starting keyword by adding letters and numbers before and after it, then searching Pinterest for each one and showing you all of the searches Pinterest suggests to users.

For example:

Initial keyword: Chocolate cake

Our tool then queries Pinterest's search engine for "Chocolate cake" and we grab all of the "search suggestions" Pinterest shows users. These are the most related and popular keywords/searches for your initial keyword.

Next, our tool then queries Pinterest's search engine for "chocolate cake a" and we grab all of the search suggestions Pinterest shows users. E.g., "chocolate cake and ice cream" may be one of the suggestions that appears:

We repeat this process for every letter of the alphabet and then numbers 0-9. We do this before and after your initial keyword.

The first set of keyword results you see are the ones that Pinterest immediately suggested for just your initial keyword. These are excellent keywords to start with because they're likely more searched and popular.

I recommend you choose a keyword you want to narrow down and click on it to perform an even more narrow, long-tail search on Pinterest to see which keywords it suggests. Then, sort the results by popularity.