If you want to revise a particular word list in the lead-up to an exam, it is important to keep the words together in one place, so that they can be studied with 'ranged testing'. The preferred approach is to enter the words into a list ('.lst') file and then import the list file into your main vocab file. This way, the word list can easily be printed out or shared with other students.
To study with ranged testing, use the 'Test range...' option under the 'Testing' menu heading, instead of just pressing the 'Test' button. You will be asked to enter the first and last item numbers to be revised (such as '1001-1050' to revise items 1001 to 1050). A fancier approach, recommended for teachers, is to give the first item in the list ('.lst') file a Grammar/Footnote tag, such as 'Week 5 words' and the last item an 'END' tag. The list can then be accessed by name instead of by number. It can also be added as a theme under the Themes menu. When using the 'Test range' feature, only items within the indicated range will be tested, and all other items will be ignored. The exam items are still part of the overall vocab, however, and will be scheduled for revision over the coming weeks and months, like every other item.