Searches not working on Reverse Proxied Site

Hi,

Am reverse proxying "journals.aps.org". But to my surprise searches thru its search bar don't yield any result.

My ngnix.conf is like,


server {
listen MY_IP:80;
server_name journals-aps-org-MY_DOMAIN;
location / {
return 301 https://$host$request_uri;
}
}
server {
listen MY_IP:443 ssl;
server_name journals-aps-org-my.domain;
ssl_certificate /etc/nginx/ssl2017/nginx.crt;
ssl_certificate_key /etc/nginx/ssl2017/star.my.domain.key;
location / {

proxy_bind MY_IP;

proxy_pass https://journals.aps.org/;
}

location ^~ /error/ {
internal;
root /etc/nginx/html;
}

location /libs/mathjax/2.7.2/MathJax.js {
proxy_pass https://cdn.journals.aps.org;
}
}


Any help would be really needful.