In spreadsheets and documents in which form controls are used, you can click the Find Record icon on the form bar to open a dialog to find any text and values.
You can search in one or in all data fields. You can select whether the text must be at the beginning, end or any location of the data field. You also can use the ? and * wildcards, as in the Find & Replace dialog. You can find additional information about the database search function in the LibreOffice Help.