nginx rewrite for 2 blogs?

web server is nginx + fastcgi php + mysql
blog platform is wordpress

I have 2 blogs:
https://domain.com/blog on /var/www/nginx-default/blog
and
https://domain.com/blog2 on /var/www/nginx-default/blog2

here is my current “/etc/nginx/sites-available/default”

server {
listen 80;
server_name localhost;
root /var/www/nginx-default/;
access_log /var/log/nginx/localhost.access.log;

location / {
index index.html index.htm index.php;
if (!-e $request_filename) {
rewrite ^/blog/(.+)$ /blog/index.php?q=$1 last;
}
}
}

if i use this setting above, blog2 will be “404 not found”
how to update the “/etc/nginx/sites-available/default” for both blogs under the same directory?