When searching for a specific artist in NASCAT, always enter the last name first. Such as: Cassatt, Mary.
Use Words in Subject as your search type. This will give you all of the books, videos, etc. that the library owns about Mary Cassatt. If you were to use Words Anywhere instead of Words in Subject, your results would include every item the library has that mentions Mary Cassatt.
When searching NASCAT, you will see the following option:
This essentially means- do you want to keep your search terms together?
For example: If you search for "tea set" you would want to select "yes" and keep your words adjacent. This would ensure that the catalog only showed you items about tea sets.
If you selected no, then the catalog would search for every item that contained the words tea or set. So your results would include: the tea party, tea production, set design, etc. and everything else that included either of those words.