Example how coins search can be used.
In case of search 'Russian Empire Nicholas II 1 ruble' it can be done in following way:
'ruble' is typed in search field - a lot of rubles are displayed.
then filter attributes are used to narrow the search result:
"Russian Emprire" is filtered.
"Nikolay II" is filtered.
"1" is filtered.
Few Nicholas II Rubles are displayed:
1/4 Noble Kingdom of England (927-1649,1660-1707) ...
Coin prices from public sources