Update u_e-dovecot-fts.md

docs/u_e-dovecot-fts.md

@@ -20,13 +20,16 @@ Dovecot Wiki: "Scan what mails exist in the full text search index and compare t
 
 This does **not** re-index a mailbox. It basically repairs a given index.
 
-If you want to re-index a users data, you can run the followig command, where '*' can also be a mailbox mask like 'Sent':
+If you want to re-index data immediately, you can run the followig command, where '*' can also be a mailbox mask like 'Sent'. You do not need to run these commands, but it will speed things up a bit:
 
 ```
+# Single user
 docker-compose exec dovecot-mailcow doveadm index -u user@domain '*'
+# All users, but obviously slower and more dangerous
+docker-compose exec dovecot-mailcow doveadm index -A '*'
 ```
 
-This **will** take some time depending on your machine and Solr may even run oom.
+This **will** take some time depending on your machine and Solr can run oom, monitor it!
 
 Because re-indexing is very sensible, we did not include it to mailcow UI. You will need to take care of any errors while re-indexing a mailbox.