There are a few workarounds we can try to employ to get you the results you are looking for:
  1. Contact Support and reference this article. 
  2. Rebuild the query or report (or have support help you rebuild the query or report) to involve fewer queries, criteria, or report columns
  3. If there are a large number of results expected in the report, schedule it to run overnight
  4. Add criteria to the query to help segment the results into smaller, more manageable results