Different between cron.php and /admin/reports/status/run-cron

My drupal's version is 6.3
It installed CCK, and add a fileld ( field_tags ) in "page" content type. I created some pages. I found a problem when I search these pages:

crate page1 :
title : title1
body: body1
field_tags( by cck created ): tags1
run http://localhost/admin/reports/status/run-cron , then type "tags1" to search the page , It works.

But :
crate page2 :
title : title2
body: body2
field_tags( by cck created ): tags2
run http://localhost/cron.php , then type "tags2" to search the page , It didn't work, can't find the page.Only type title2 ,can search it.

why ?
How can I run http://localhost/cron.php ,Let it works.