It can be useful to be able to locate and examine all todo items that fit certain criteria, regardless of which category they belong to. One way to do this in Todo mode is by sequentially searching in the file:
This command (todo-search; the key is capital S) prompts for a
regular expression, searches from the beginning of the current todo file
and displays the category containing the first match it finds, with the
match highlighted. If there are further matches, a message saying how
many are left is displayed and you are asked if you want to go to the
next match. When you reach the last match, or if you decide not to go
to further matches, you are asked whether the match highlighting should
be removed.
This command (todo-clear-matches) removes any highlighting added by S.
This is so you can leave the matches highlighted at the end of the
search and remove the highlighting later.
These commands are also available in Todo Archive mode.