EDIT:
From a quick glance at the source code for the homepage, you can see some references to non-secure (HTTP) resources. See below for a snippet:
DXImageTransform.Microsoft.AlphaImageLoader(src='http://epharmacies.com/wp-content/uploads/2015/04/eDS-blue-pill-bg-2.png'
background-image:
url(http://epharmacies.com/wp-content/uploads/2015/04/eDS-blue-pill-bg-2.png);">
SSL/Certificate Tools
Comodo SSL Certificate Troubleshooter
The lock with yellow warning triangle icon signifies that although the connection to the site is encrypted, there are other resources on the page which are not secure, which can be viewed by others while in transit and modified by an attacker to change the look of the page.
From Google's documentation:
Site Identity information:
Google Chrome can see the site’s certificate, but the site uses a weak
security setup (SHA-1 signatures), so your connection might not be
private.
Proceed with caution. These are common mistakes in websites'
configurations, but that doesn't guarantee that your connection is
secure.
Connection information:
Your connection to the site is encrypted, but Google Chrome has found
something on the page that could be
unwanted images or ads. We suggest you don't enter private or personal
information on this page.