Well... Then that's a severe issue.
In that case, I would strongly urge to order online and buy from some reputed websites, which sell genuine products, like Daraz. For Zic, you can order online via their official website; http://zicoil.pk/ I think, they offer free home delivery.
Best suggestion regarding any product (be it engine oil) would be, directly contact the company! They have their official, local websites and contact details are there. Just call them, mention your city i.e. Quetta, and discuss the problem you are facing. e.g. regarding engine oil, you can call Total Parco helpline and ask them to guide you about their biggest retailer / wholesaler / dealer in Quetta, which sell the products.
They will very happily guide you. Their products will get sold and you will also do their publicity, what else would they need? 
I believe, there will definitely be reputed shops and markets in the beautiful city of Quetta, which sell genuine products. You just need to figure them out.