GOOGLE BLOGGER IS MOST POPULAR BLOG SITE FOR BLOGGER. GOOGLE BLOGGER DOES NOT SUPPLY ANY META DESCRIPTION BY DEFAULT . META DESCRIPTION AND META KEYWORDS CONTAIN WEBSITE BASIC INFORMATION THAT HELP MANY SEARCH ENGINE TO CRAWL YOUR WEBSITE. MANY SEARCH ENGINE SEARCH WEBSITE ON BASE OF META TAG. SO YOU NEED TO ADD META TAG MANUALLY TO YOUR BLOGSPOT BLOG. TO ADD META TAG TO YOUR BLOG FOLLOW THESE STEP:
1. LOG IN BLOGGER
2. CLICK ON DESIGN
3. CLICK ON EDIT HTML
4. CHECK 'EXPAND WIDGET TEMPLATE'
5 . NOW FIND :
1. LOG IN BLOGGER
2. CLICK ON DESIGN
3. CLICK ON EDIT HTML
4. CHECK 'EXPAND WIDGET TEMPLATE'
5 . NOW FIND :
<b:include data='blog' name='all-head-content'/>6. WRITE YOUR META DESCRIPTION AND META KEYWORDS 
THEN CLICK SAVE TEMPLATE
I found some useful tips. Many thanks for posting.