This search page employs an advanced search tool called Relevansii that runs within the website itself. This tool has indexed the content of all pages on the site but not the content of uploaded documents, such as PDF's. (Note that external search engines, such as Google, will search within PDF documents.)
Since information about photographs on the site is generally shown in the text of the page(s), you can also search for people or places named in photographs.
Advanced Search notes:
By default the AND operator is used for the whole query and if there are no results then the OR will be tried. In other words by default all search terms will be tried, resulting in a list of pages that contain all the terms and only if there are no results will each search term be tried on its own.
Very short words of less than 3 letters are excluded from the index as are around 300 common words such as "everyone", "several" and "between".
You cannot use the NOT operators for search terms to exclude pages that contain that word from the results nor conduct complex searches with dates, such as to find pages containing dates in the range "1974-1976". Nor can you use complex bracketed queries like "(cats OR tigers OR lions) AND (pumas OR cougars) NOT dogs".
If there are no results for the whole words in the query then partial words will be tried, meaning words that begin or end with the search term. Results are presented in oreder of relevance so for example where the search terms are found in the page title, then these will come first in the results list, followed by those pages that contain all of the search terms. The results each consist of a snippet where the successful search terms are shown in bold if they appear in the snippet itself. Search results are limited to the first 500 pages containing the terms.
So for example you can search for "cricket" and get around 230 results, or search for "cricket 1974" and get around 90 results containing both those words. You can search for "cricket 1974 douglas" and get twenty results or search for "cricket 1974 doug" and get just two results that include the shortened version of the name (and the full version as a partial match).