Htaccess - Exclude a word from existing rewrites - .htaccess

Question

I have the following in my htaccess file:
# drop tags
#RewriteCond %{THE_REQUEST} (.*)designs/(.*)/?tag=shirts [NC]
#RewriteRule .* /designs/%2/ [R=301,L]
RewriteCond %{THE_REQUEST} (.*)designs/([^?]+)\?tag=[^&]* [NC]
RewriteRule .* /designs/%2? [R=301,L]
# external redirect from actual URL to pretty one
RewriteCond %{THE_REQUEST} \s/+product/search/\?tag=([^\s&]+) [NC]
RewriteRule ^ /%1/? [R=301,L,NE]
# internal forward from pretty URL to actual one
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !^/designs/ [NC]
RewriteRule ^([^/]+)/?$ product/search/?tag=$1 [L,QSA]
RewriteCond %{QUERY_STRING} ^search= [NC]
RewriteRule ^designs/.*$ /$0? [L,R=301,NC]
RewriteCond %{QUERY_STRING} ^mfp= [NC]
RewriteRule ^designs/ %{REQUEST_URI}? [L,NC,R=301,NE]
My theme supports a blog but after enabling it (it defaults to example.com/blog/), when I click on the blog link in my menu, it takes me to a page that says "There is no product that matches the search criteria". When I remove the htaccess rules listed above, the blog page (which contains the article listings) works fine so it is definitely that.
How can I exclude the word "blog" from the htaccess rules so this issue disappears?

Answer 1

I managed to fix it after a couple hours of tinkering. The solution was:
# external redirect from actual URL to pretty one
RewriteCond %{REQUEST_URI} !^/blog($|/)$
RewriteCond %{THE_REQUEST} \s/+product/search/\?tag=([^\s&]+) [NC]
RewriteRule ^ /%1/? [R=301,L,NE]
# internal forward from pretty URL to actual one
RewriteCond %{REQUEST_URI} !^/blog($|/)$
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} !^/designs/ [NC]
RewriteRule ^([^/]+)/?$ product/search/?tag=$1 [L,QSA]
This solution also handles /blog (without the trailing /).
Hope that helps someone in the future.