You can search text as in most programs using the Find dialog.
You can open this dialog by selecting Edit->Find or pressing (shortcut: CTRL+F).
The search string can be entered in the Search for text field.
By default, the search is case insensitive - for example, searching for "Hello" will match "hello", "HELLO" and "HeLlO". You can mark Match case to enforce hit exactly the same case as the query.
The Direction determines to what relative direction of the cursor will be searched. Forward means text beyond the cursor will be searched, Backward means text before the cursor will be searched.
The Search mode determines how the query will be handled: