These corpora are prepared from specific domains, e.g. science, art etc. Thanks to that, you can study specifics the certain domain. Domain specific corpora built using WebBootCat and Dante lexical database.
Other details are in the Domain Web Corpus page.
List of corpora:
CAJA (academic journal articles)
COMPAS (newspaper dailies related to immigration)
Environment (restricted access)
Medical Web Corpus (medical)
TECU (geodetics, development)