To seach words in a note, tap button.
Tap inside the search field, and enter keyword to search. Tap "Seach" button to find the resuld.
When search results appear, tap "Replace Mode".
Then Replace window appears below search window. Enter the word you like to replace and tap "Next"button.
Tap "Replace"button to substitute a searched keyword to the word you entered.
If you tap "Replace All" button, you can replace all keywords within a note.
Tap "Done" button to finish searching.