C-s searches forward and C-r searches backwards in the current buffer. Type the query, listen to the match feedback, and repeat the search key to reach another occurrence. Reverse direction with the other search key when you overshoot. Searching the current text does not send a web or mail query.
When you find the occurrence you want, press RET to end the search before typing document text. Forward search leaves point after the match; backward search leaves it before the match. Check with C-e l before editing. With a failing search, C-g first backs out of the failed part; another C-g may be needed to abandon the search. Do not begin an edit while its prompt is active.
For details of repetition, search history, case and failure recovery, use Incremental search in the GNU Emacs Manual. Its rules describe the editor; Emacsvox adds spoken match context and search cues. The next procedure changes text, so it begins by establishing a narrower scope.