Scholarly journals from throughout the 20th century are spread across many databases. Google Scholar rarely includes this 20th century material that was not 'born digital.' The best way to quickly search across as many 20th century scholarly journals as possible is to use Articles+
The trickiest part is identifying the best words to use for a search. If one were interested in finding information about the Freeman/Watts lobotomy, they could try searching for:
Very Important: after running your search use the "Publication Date" filter to limit to the nears that interest you. For example you can limit from the years preceding to the years directly following Rosemary Kennedy's lobotomy. You need to click on the pencil icon to be given the option to select a date range. You also have the option to limit by discipline. For example, you can look at only the articles classified as psychology, medicine, public health, and so on.
