The Find in notebook dialog enables to find a text in any part of the current notebook. To find the desired text, you can use the regular expressions syntax.

First, specify a Text to find in a edit box. You may choose any of the previously searched text from drop-down combo.

Than choose where to find:
Current note + sub notes - search through current note and all its child notes.
Current notebook - search the entire notebook, currently active.
All opened notebooks - search in all opened notebooks.

Now set up search options:
Use regular expressions - enables to use powerful regular expressions syntax to search in notes.
Case sensitive - do not ignore text case (CAPITAL or small letters) when doing the search.
Whole words only - treat text to find as a word and do not perform search for it as a part of other words.
Match mode - if text to find consists of more than one word, so:
   Exact phrase - look for these words as a monolith phrase.
   Any of these words - the result will match if any of the words is present in the note.
   All of these words - the result will match if all of the words is present in the note.

Search results are formatted in the table. Note column shows the notebook and note where the text was found. First text match concurs with the first text piece that matches the 'text to find'. Rank column are nonzero only when searching with complex regular expressions.

My Notes Center also searches in note names (in tree). If the 'text to find' matches with note name, it appears bold in results table.

Double-click to note in search results table to jump to it. Also it is possible to minimize Find in notebook window instead of closing to keep the search results.