diff --git a/runtime/doc/tabpage.txt b/runtime/doc/tabpage.txt
index a30d3a1..a2da5b3 100644
--- a/runtime/doc/tabpage.txt
+++ b/runtime/doc/tabpage.txt
@@ -173,10 +173,20 @@
 REORDERING TAB PAGES:
 
 :tabm[ove] [N]						*:tabm* *:tabmove*
+:[N]tabm[ove]
 		Move the current tab page to after tab page N.  Use zero to
 		make the current tab page the first one.  Without N the tab
 		page is made the last one.
 
+:tabm[ove] +[N]
+:tabm[ove] -[N]
+		Move the current tab page N places to the right (with +) or to
+		the left (with -).
+
+Note that although it is possible to move a tab behind the N-th one by using
+:Ntabmove, it is impossible to move it by N places by using :+Ntabmove. For
+clarification what +N means in this context see |[range]|.
+
 
 LOOPING OVER TAB PAGES: