You may also need to use multiple RewriteCond lines if the parameters are not always in the same order.

Code:
RewriteCond %{QUERY_STRING} main_page=document_product_info
RewriteCond %{QUERY_STRING} cPath=34
RewriteCond %{QUERY_STRING} products_id=130
RewriteRule ^index.php$ http://mysite/index.php?main_page=about_us [R=301,L]