See Beyond Price - All Sale Prices

An ordinary search STARTS WITH your text.
Put a * infront of your text to search for all cards INCLUDING the word, eg :

"Vigor" returns Vigor, Vigor Mortis...
"*Vigor" returns Amulet of Vigor, Crown of Vigor...

Add the tag "s:" (or "set:" "e:" "edition:" which all do the same thing)
This tag can be before or after your card name, and does not apply to sets

"S:M19 shock" will return all variants of M19 shock - eg, foil, non foil

Use the tag "is:"
This tag can be before or after your card name, and does not apply to sets
Allowable finishes - Foil, NonFoil, Etched, NonEtched

Adding "is:foil" will return only FOIL variants of any results

Use the tag "cn:" (or "number:")
This tag returns only cards with the specified collector number
This suppresses any sets matching the text entered (as sets do not have a collector number)

Adding "cn:100" will return only cards with collector number 100