As hard as nails

If something is as hard as nails, it is very strong. If somebody is as hard as nails, they tend not to feel sympathy or other positive emotions.

Be much put about (be troubled or worried)
I was much put about by the news.

Put an idea across (persuade people to accept it or approve of it)

Come about
When something comes about, it happens without planning.

I don’t know how these things come about.
It was an unexpected discovery that came out while scientists were working on a different project.

Call a spade a spade
When you call a spade a spade you speak directly and precisely.
Only the courageous can call a spade a spade.
Call into question
To call into question is to challenge the accuracy or probity of something.
We shouldn’t call her sincerity into question.
We can’t call her qualifications into question.
Because of her poor performance, we had to call her competency into question.

Go is used before a number of adjectives to talk about changes. This is common in an informal style.
Go, for example, is used to talk about changes of color. This usage is common in British English.
Examples are: go brown, go green, go white, go black, go blue etc.

Hang on to something

To hang on to something is to keep something.

Take the bull by the horns (face a difficult situation boldly)

Why don’t you take the bull by the horns and dismiss him.