Even when your site is on the regular crawl schedule, only one or two pages are updated in a day. When your site has a proper XML sitemap, all the major bots will crawl the sitemap to get a list of your pages. When you post a new map with added pages, those pages will be crawled within a couple of weeks. When your sitemap uses the optional "lastmod" tag, the bots can concentrate on crawling only the pages with edits, saving everyone bandwidth, and getting your latest changes to the SERP faster.
The Harvestman verbose report will show the contents of the description meta-tag, if any. If you don't have a description meta-tag, Harvestman will report a "snippet" from the start of the page-body. Google (and most other search sites) will also provide (much smarter) snippets if your descrition is missing or short.
This actual example of a page source, the Verbose report of the page, and Google's SERP entry, is presented to aid you in using a Verbose report of your site to see what needs tweaking BEFORE Googlebot comes to call.
For best effect, DONT post a sitemap with updated lastmod for a page untill you like what you see in the Verbose Report.
<html><head><title>Harvestman Control section</title> <meta name="description" content="Harvestman User's guide, control section"> . . . </head> <body class="c7">
http://can2can.biz/Content/Spider/control.html :: Title=Harvestman Control section :: Keywords=:: :: Description=Harvestman User's guide, control section :=:
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