Here are the possible solutions for they may be hard to crack clue
Answer
Clue
Relevancy
safes
Clue
They may be hard to crack
try
Clue
Crack or shot, but not crack shot
nuts
Clue
They might be hard to crack
Definition
NUT, to gather hard-shelled dry fruit
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