You need to toughen up if you want to succeed in this competitive industry.

These tougher nuts to crack require more effort to solve.

She is a tougher nut to crack than I thought.

He is the toughest nut to crack in the team.

These problems are the toughest nuts to crack.

The glass is toughenable through a special heating process.

She approached the problem toughmindedly, refusing to let emotions cloud her judgment.

She is a toughminded leader who always makes rational decisions.

Her toughmindedness helped her overcome many obstacles.

The toughenings on the surface of the metal provide extra strength.