The search on both your website and on the admin space look into all of your images' metadata (keywords, caption, location...), but they work in different ways.
When you search for images within your admin space (My Images & Videos), the system looks for exact matches. For example, a search for cats will not return and image with the keyword "cat". Partial matching and wildcards are not supported.
Tip: to look for an image, enter its ID. The ID of an image is its filename, without the .jpg/.tif extension.
You can limit the search to look only at keywords instead of the whole metadata by using the keywords search field.
You can also save a search as a Smart Collection. The internal admin search is also used by the automation features.
The search is NOT case-sensitive. It looks at the following metadata: image ID (filename minus its .jpg/.tif extension), title, description, location, city, country, state, region, keywords, author.
On your website, the search looks at the same metadata fields, but is much more sophisticated. For example, it knows plurals, so a search for cats will return images with the keyword "cat". It relies on a separate image search index, that is updated separately.
As a consequence, it can take a couple of hours before new images / new keywords appear in the search on your public website.
This applies to both the search in the admin space and the search on your website.
Boolean operators help you or your visitor refine their search. For instance:
When your galleries contain very similar images, you can group results by galleries via My Website / Setup / Advanced settings.
This way, when performing a search, your client gets the list of galleries having images that match, along with the number of results of matches per gallery.
You can display a search box on any website by adjusting and pasting the following piece of HTML code (replace YOUR-PHOTODECK-URL-HERE by your own website URL):
<form accept-charset="UTF-8" action="///YOUR-PHOTODECK-URL-HERE" method="get">
<div style="margin:0;padding:0;display:inline"><input name="utf8" type="hidden" value="✓"></div>
<input name="search" placeholder="Image search" type="search">
<input name="commit" type="submit" value="Go">