ServiceNow Grab Detailed Logs

go to:

https://<instance_name>.service-now.com/ui_page_process.do?name=log_file_browser

and specify a time range, e.g. 

results:

you can also specify message content or thread name for example:



see also: https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0958075