diff --git a/gui-doc/scribblings/framework/text.scrbl b/gui-doc/scribblings/framework/text.scrbl
index f2deb619..14653a69 100644
--- a/gui-doc/scribblings/framework/text.scrbl
+++ b/gui-doc/scribblings/framework/text.scrbl
@@ -539,7 +539,7 @@
 @definterface[text:searching<%> (editor:keymap<%> text:basic<%>)]{
   Any object matching this interface can be searched.
 
-  @defmethod[(set-searching-state [str (or/c #f (and/c string? (not/c "")))]
+  @defmethod[(set-searching-state [str (or/c #f non-empty-string?)]
                                   [cs? boolean?]
                                   [replace-mode? boolean?]
                                   [notify-frame? boolean?])
diff --git a/gui-doc/scribblings/gui/text-class.scrbl b/gui-doc/scribblings/gui/text-class.scrbl
index 76561e86..eedb430d 100644
--- a/gui-doc/scribblings/gui/text-class.scrbl
+++ b/gui-doc/scribblings/gui/text-class.scrbl
@@ -637,7 +637,7 @@ can be any of the following:
 }
 
 
-@defmethod[(find-string [str string?]
+@defmethod[(find-string [str non-empty-string?]
                         [direction (or/c 'forward 'backward) 'forward]
                         [start (or/c exact-nonnegative-integer? 'start) 'start]
                         [end (or/c exact-nonnegative-integer? 'eof) 'eof]
@@ -668,7 +668,7 @@ If @racket[case-sensitive?] is @racket[#f], then an uppercase and lowercase
 
 }
 
-@defmethod[(find-string-embedded [str string?]
+@defmethod[(find-string-embedded [str non-empty-string?]
                                  [direction (or/c 'forward 'backward) 'forward]
                                  [start (or/c exact-nonnegative-integer? 'start) 'start]
                                  [end (or/c exact-nonnegative-integer? 'eof) 'eof]
@@ -690,7 +690,7 @@ If @racket[case-sensitive?] is @racket[#f], then an uppercase and lowercase
        search result position.
 }
                                                 
-@defmethod[(find-string-all [str string?]
+@defmethod[(find-string-all [str non-empty-string?]
                             [direction (or/c 'forward 'backward) 'forward]
                             [start (or/c exact-nonnegative-integer? 'start) 'start]
                             [end (or/c exact-nonnegative-integer? 'eof) 'eof]
@@ -704,7 +704,7 @@ Finds all occurrences of a string using @method[text% find-string]. If
 
 }
 
-@defmethod[(find-string-embedded-all [str string?]
+@defmethod[(find-string-embedded-all [str non-empty-string?]
                                      [direction (or/c 'forward 'backward) 'forward]
                                      [start (or/c exact-nonnegative-integer? 'start) 'start]
                                      [end (or/c exact-nonnegative-integer? 'eof) 'eof]