For better results when searching notes, consider the following tips:
Use uppercase and lowercase letters interchangeably Searching in OneNote is not case sensitive. For example, if you type “Monday”, OneNote finds all notes that contain both “Monday” and “monday”.
Use only the first few letters of a word to expand your search results When you type the first few letters of a word, OneNote finds any words that contain those letters. For example, if you type “Tim” and you have notes that include the word “time”, OneNote finds all notes containing both “Tim” and “time”.
Use "audio recording started" or "video recording started" to find audio or video notes When you record audio or video notes, OneNote automatically inserts the text "Audio recording started" or "Video recording started," depending on the type of recording. To search for audio notes, type audio recording started. To search for video notes, type video recording started.