your blood is far too thin

[dilermando]

Hello,

A real crook is trying to mary a woman, but she hates him. She tells to him "your blood is far too thin".

What did mean by saying that?

[BobK]

It's not a usage I've met, but it may have something to do with heartlessness...

b

[dilermando]

The man had said to her before that he want to have a lot of children with her. Maybe this makes some difference. I don't know. I do not understand.

[Offroad]

let me guess...

the opposite of thin is thick... I found this idiom on the internet:

blood is thicker than something

meaning:
family relationships are stronger and more important than something else.

example:
We were old friends, but I couldn't side with her against my parents — blood was thicker than friendship to me.

My guess:
The woman says the man is not the right person to have a child with, there's no chemistry between them.

[Anglika]

It is far more likely that she either means that the person is physically weak or that he is of an undesirable social group.

Thin blood was taken to indicate a low system - whereas good, thick red blood indicated good health.

[RonBee]

blood is thicker than something

The expression is:

Blood is thicker than water.

That means that family relationships are more important than any other kind.

[Raymott]

Hello,

A real crook is trying to mary a woman, but she hates him. She tells to him "your blood is far too thin".

What did mean by saying that?

If the guy is a crook, and this woman is a (potential) gangster's moll, she is concerned about his ability to stand up to the inevitable violence of their lifestyle.
At a literal level, bad guys who get beaten up and bleed a lot need thick blood to recuperate. Or perhaps he's been shot too many times already.
At a metaphorical level, it might mean something to do with his masculinity - perhaps he is cowardly.

In other words, I don't know either

[Offroad]

The expression is:

Blood is thicker than water.

That means that family relationships are more important than any other kind.

blood is thicker than something
family relationships are stronger and more important than something else. We were old friends, but I couldn't side with her against my parents — blood was thicker than friendship to me

Blood is thicker than water. something that you say which means family relationships are stronger and more important than other kinds of relationships, such as being friends. They say blood is thicker than water, so how come so many families hate each other?

[dilermando]

If the guy is a crook, and this woman is a (potential) gangster's moll, she is concerned about his ability to stand up to the inevitable violence of their lifestyle.
At a literal level, bad guys who get beaten up and bleed a lot need thick blood to recuperate. Or perhaps he's been shot too many times already.
At a metaphorical level, it might mean something to do with his masculinity - perhaps he is cowardly.

In other words, I don't know either

The girl is a very nice person. She is one of the good guys.

[RonBee]

Blood is thicker than water.

The phrase has an interesting history. (The phrase blood is thicker than something is based on the older blood is thicker than water.)

Blood is thicker than water - Wikipedia, the free encyclopedia
GoEnglish.com Idioms = "Blood Is Thicker Than Water" = Today's English Idioms