Help with the HEIDI online catalogue of the University Library Heidelberg searchable items

In the HEIDI Online Catalog, media available at the University Library Heidelberg and the decentralized libraries are listed:

• Collections of the University Library from the publication year 1962 onwards
  Older works are displayed in a parallel result list from the digitized card catalog (partial collection from 1936-1961).
• Complete newspapers and journals
• Complete holdings of the decentralized libraries fully listed from the publication year 1990 onwards

For collections published before 1962, please also consult the other catalogs in our library system.

• “Articles & more” is based on the web-scale discovery service 'Summon' by Exlibris/Proquest and indexes numerous journals and full-text databases. The Summon index currently provides access to around 40 million titles (e-books, e-journals, and databases) with approximately 4 billion records. However, when using the "Articles & more" tab, only products licensed by Heidelberg University are included in the index.
• If you activate the option “Add results beyond Heidelberg libraries collection” in the left control bar, the entire index is taken into account, i.e. there is no longer a restriction to the content licensed by the university. Please note that in many cases the full texts behind the hits are not available for members of Heidelberg University.
• “Articles & more” include texts in a variety of languages, it is advisable to enter search terms in various languages.