Citation counts for books and book chapters can be found in the same way as for other publication types (See Metrics for individual publications).
But, it may be more troublesome to verify the citation counts for book chapters. This happens because often there are inaccuracies and inconsistencies in the referencing data for Books (date, author and edition variations) or for Book Chapters (book v book chapter cited, plus errors and variations).
Data for these publication types often mainly occurs via Google and Google Scholar. But commercial data sources aren't able to harvest and integrate data from Google. It causes additional difficulty to add up citation counts for books/book chapters up accurately.
You may need to rely on additional indicators of the prestige, impact, calibre of your book and book chapters and be able to demonstrate that in words (case based reasoning).
When it is difficult to track citation counts for books/book chapters via the tradition citation indexes (Web of Science, Scopus, or Google Scholar), consider using other discipline specific tools to supplement your searches to track evidence.