Please have look down the rejection toursit visa to us I applied 4 years ago

Please have look down the rejection toursit visa to US I applied 4 years ago and the rejection was you do not have strong sufficient ties to outside of US such economic and family professional education
As per their saying that I didnt meet the requirement.
But now I already applied again and they ask me on the application
Have ever been refused visa to Us YES or NO I answered YES
Explain ? so I need to explain to them
Please your advice