Search through all subsequent articles for a regexp (gnus-summary-search-article-forward).

Search through all previous articles for a regexp (gnus-summary-search-article-backward).

This command will prompt you for a header field, a regular expression to match on this field, and a command to be executed if the match is made (gnus-summary-execute-command). If given a prefix, search backward instead.

Perform any operation on all articles that have been marked with the process mark (gnus-summary-universal-argument).