Not many people can commit such heinous crimes in ________.

• Cold blood (idiom):   
- English Meaning: without emotion or pity / deliberately cruel or callous.
- Bangla Meaning: নৃশংস ভাবে, খুব ঠান্ডা মাথায় কিছু করা।    

Ex. Sentence: Not many people can commit such heinous crimes in cold blood.
Bangla Meaning: খুব বেশি মানুষ ঠান্ডা মাথায় এমন জঘণ্য অপরাধ করতে পারে না।

• Other options, 
- Cold War: A conflict over ideological differences carried on by methods short of sustained overt military action and usually without breaking off diplomatic relations.
- Close-fisted: Unwilling to spend money/means.

Source: Website lecture.