Something bought unseen's like poking a pie, unfortunately (3,2,1,4)
I believe the answer is:
pig in a poke
'something bought unseen's' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.
'poking a pie unfortunately' is the wordplay.
'unfortunately' indicates anagramming the letters (a bad or unfortunate spelling).
'poking'+'a'+'pie'='pokingapie'
'pokingapie' is an anagram of 'PIG IN A POKE'.
'like' acts as a link.
Can you help me to learn more?
(Another definition for pig in a poke that I've seen is " Blind purchase".)