Variable: org-agenda-search-view-search-words-only
org-agenda-search-view-search-words-only is an alias and customizable
for org-agenda-search-view-always-boolean, defined in
org-agenda.el.gz.
Value
nil
Documentation
Non-nil means the search string is interpreted as individual parts.
The search string for search view can either be interpreted as a phrase, or as a list of snippets that define a boolean search for a number of strings.
When this is non-nil, the string will be split on whitespace, and each
snippet will be searched individually, and all must match in order to
select an entry. A snippet is then a single string of non-white
characters, or a string in double quotes, or a regexp in {} braces.
If a snippet is preceded by "-", the snippet must *not* match.
"+" is syntactic sugar for positive selection. Each snippet may
be found as a full word or a partial word, but see the variable
org-agenda-search-view-force-full-words.
When this is nil, search will look for the entire search phrase as one, with each space character matching any amount of whitespace, including line breaks.
Even when this is nil, you can still switch to Boolean search dynamically by preceding the first snippet with "+" or "-". If the first snippet is a regexp marked with braces like "{abc}", this will also switch to boolean search.