Visitor Visa - B2

Hi all,I just wanna share my experience and need suggestions
I am on L2 visa and my husband is on L1. He sponsered them in documents
 My parents & brother visa refused today. my dad and brother both are central govt.emplyoees in xyz organisation
And my mom is a house wife. They went together for interview and VO started with my mom.
VO was black American rude lady who interviewed them.she was asking in hindi and English both. We scheduled appointment in hindi because of my mom. Sh is the only one who was interviewing them in both languages.
As per my knowledge they just want strong ties in home country.

Question she asked to my mom
VO:where are u going ?
Mom: xyz ,ca
VO: what does your daughter do ?
Mom: she was working before but now she is house wife..(that was not a suspicious question for denial )
She got nervous because VO started with her.

Question asked with brother:
VO: where are you going?
Brother : replied well
 VO:What do u do?
Brother:I work as a govt.emplyoee in xyz organisation on this designation
VO:how long would u stay ?
Brother:3 weeks
VO: What does your brother in law do?
Brorher:he works in xyz company as a solution architect.

Questions asked with dad
VO:same question as brother.

At the end she said I cant approve visa...
My parents and brother has strong reasons to go back their home country .they have govt. Secured jobs.
She didn't ask a single document from them I dont why??
I want to reaply for them .please suggest what should I do for strong interview ??

Thanks