Research is often first communicated via conferences and their proceedings.
Conference papers are often published in journals to be found in online databases.
Some databases will let you limit your search to just conference proceedings, but you will generally have to add the terms
proceeding* to your search words.
Plan your search and use search engine tricks to get the best results.
coal mining and (conference* or proceeding*).
This search string looks for any conferences and their proceedings relating to the coal mining industry.