In general, if statements should be avoided when possible, particularly inside location blocks. From the aptly titled "If Is Evil":

Directive if has problems when used in location context, in some cases it doesn't do what you expect but something completely different instead. In some cases it even segfaults. It's generally a good idea to avoid it if possible.

The only 100% safe things which may be done inside if in location context are:

• return ...;
• rewrite ... last;

Anything else may possibly cause unpredictable behaviour, including potential SIGSEGV.

As to your specific question, you can leverage regex to have multiple matches in the condition but not multiple conditions. So you can do something like:

if ($geoip_country_code ~ (BR|CN|KR|RU|UA) ) {
    # Do something
}

but not:

if ($geoip_country_code ~ (US|CA) ) | ($http_cookie ~* "CCCC=.+(?:;|$)"  ) {
    # Do something else
}

There are some workarounds using multiple if statements. Check out this post.

You can also use something like:

    if ($request_uri = /) {
      set $test "root";
    }

    if ($host ~* zencocoon.com) {
      set $test  "${test}+zencocoon.com";
    }

    if ($http_cookie !~* "auth_token") {
      set $test  "${test}+no_auth_token";
    }

    if ($test = "root+zencocoon.com+no_auth_token") {
      proxy_pass http://www.zencocoon.com;
      break;
    }

Taken from https://gist.github.com/jrom/1760790

http://rosslawley.co.uk/archive/old/2010/01/04/nginx-how-to-multiple-if-statements/