diff --git a/doc/emacs/search.texi b/doc/emacs/search.texi
index 6345b1b8988..70bb6b04abd 100644
--- a/doc/emacs/search.texi
+++ b/doc/emacs/search.texi
@@ -1125,6 +1125,18 @@ ends of the range in upper case, or both in lower case, or both should
 be non-letters.  The behavior of a mixed-case range such as @samp{A-z}
 is somewhat ill-defined, and it may change in future Emacs versions.
 
+To search for raw bytes (@pxref{International Chars}) using regular
+expressions, specify their codepoints in the bracket expression, as in
+@w{@kbd{C-M-s [ C-x 8 @key{RET} 3fff80 @key{RET} - C-x 8 @key{RET}
+3fffff @key{RET} ]}}.  Emacs will show the equivalent
+
+@example
+Regexp I-search: [\200-\377]
+@end example
+
+@noindent
+in the echo area.
+
 @item @kbd{[^ @dots{} ]}
 @samp{[^} begins a @dfn{complemented character set}, which matches any
 character except the ones specified.  Thus, @samp{[^a-z0-9A-Z]} matches
diff --git a/doc/lispref/searching.texi b/doc/lispref/searching.texi
index 9481782d552..a1354d30c07 100644
--- a/doc/lispref/searching.texi
+++ b/doc/lispref/searching.texi
@@ -444,6 +444,12 @@ Representations}), or if the range start is ASCII and the end is a raw
 byte (as in @samp{[a-\377]}), the range will match only ASCII
 characters and raw 8-bit bytes, but not non-ASCII characters.  This
 feature is intended for searching text in unibyte buffers and strings.
+
+@cindex raw bytes, regexps for searching
+@item
+To search for @dfn{raw bytes}, which are characters belonging to the
+@code{eight-bit} character set (@pxref{Character Sets}), you can use
+@samp{[\200-\377]} or @samp{[\x3fff80-\x3fffff]}
 @end enumerate
 
 Some kinds of bracket expressions are not the best style even