Perhaps you should try some spelling variations:
introduction comparative » production comparative, introduction corporate, introduction cognitive
programming errors » programming effort, programming reactors, programming entropy
programming expert » programming perl, programming exploits, programming experience
concept care » concepts care, concept car, concept card

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: introduction comparative ((programming errors) OR (programming expert)) concept care~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "introduction comparative ((programming errors) OR (programming expert)) concept care".
• Adding a wildcard symbol may retrieve word variants: introduction comparative ((programming errors) OR (programming expert)) concept care*.