CAUTION: See CAUTION note at end of this note before attempting the following.
This note assumes you have Windows set so that you can see the .xxx file types name extensions on the end of file names (and some folder names).
A possibility, using the Windows file system explorer, originally known in earlier versions of Windows as Windows Explorer (and My Computer), now known as File Explorer (and This PC)…
Drill/explore down into the .scriv folder containing your project, then on down into its Files subfolder. There you’ll find the searches.indexes file. It is in XML (Extensible Markup Language) format and its contents can be viewed (best) via an XML capable viewer/editor, such as UltraEdit (costs… there are free/cheaper XML viewer/editor apps available for download out there). In theory, you can view the contents in a simple text editor like NotePad, but such editors don’t understand and won’t properly lay the file’s text out for readability sake.
Within the searches.indexes file, a Document ID number corresponding the the .rtf file containing the document’s text, Title (name that it presents within Scrivener) and text (if contains any) of each individual item (folder or document) within the project will appear .
With that, you can search for the title or some text of the item you are interested in and determine the corresponding Document ID.
Note that, behind the scenes, folders and documents are actually the same underlying type of item, which present differently depending on what they are being used to represent. So what you mean by “chapter” will have a bearing on what you see. If your chapters are each contained in an individual item (typically presenting as a document), you’ll find ID, title and chapter text all together as one. If your chapters each consist of a folder containing subfolders/subdocuments, then the “chapter” folder’s ID and title will likely not have any text accompanying it… as such will be contained in individual document items each having their own ID, title and text.
CAUTION: Behind the scenes, in the file system, a Scrivener project is a database comprised of numerous files, rather than a single simple physical file. As such, poking around in or making changes, intended or unintended, to the files can result in corrupting the project. So, at a minimum, I would avoid opening the searches.indexes file, even for just viewing, while Scrivener is running or has the project open. Better yet, I would advise copy/pasting a copy of the file elsewhere, perhaps to the desktop, and viewing the contents of the copy, not the original.