Classification codes are a very broad way that articles are tagged in Business Scholarly & Trade (ABI/INFORM). For instance, there are over 80,000 articles tagged with 6200 for Training & development.
It can be useful to do a search that combines a classification code with keywords or subject terms.
emotional intelligence AND CC(62??)
This finds articles with the keyword phrase emotional intelligence that are also tagged as related to 6200 Training & Development.
(The ? marks are wildcards, meaning that any single digit number can fill those spots)
If you are looking at a research article or an empirical article, the article will most likely also have a Methods or Methodology section.