When you create a new search in SECockpit, there is an option for Google AdWords Synonyms that you can check. A field will appear where you can enter terms to omit from the search results. For example; "Attorneys Las Vegas" > omit "Lawyer" will produce a list without the term Lawyer.

If the list already exists, you may want to export the list as a csv file and open it in a spreadsheet program where you can sort and delete terms from the list as needed. Of course deleting selections in an existing list in SECockpit is also an option.