Here are the possible solutions for they might be hard to crack clue
Answer
Clue
Relevancy
nuts
Clue
They might be hard to crack
Definition
NUT, to gather hard-shelled dry fruit
try
Clue
Crack or shot, but not crack shot
safes
Clue
They may be hard to crack
ateam
Clue
Crack commando unit sent to prison by a military court for a crime they didn't commit, before escaping to the Los Angeles underground where today, still wanted by the government, they survive as soldi