Looking on the internet deeply has found these results:

I am doing business in grocery is the most popular phrase on the web.

I am doing business of grocery 11 results on the web	I am doing business in grocery 117,800,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	It's all a perfectly acceptable part of doing business in the Japanese culture. Nuisance money is the cost of doing business in my world. I advise American companies on the cultural intricacies of doing business in Mainland China. The GW has a lot of money invested in companies doing business in South Africa. I don't like him doing business in my place. He was doing business in the area. Said that was the price of doing business in Chicago. I am doing an inn business in this town!

I am doing business of grocery

11 results on the web

I am doing business in grocery

117,800,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

It's all a perfectly acceptable part of doing business in the Japanese culture.
Nuisance money is the cost of doing business in my world.
I advise American companies on the cultural intricacies of doing business in Mainland China.
The GW has a lot of money invested in companies doing business in South Africa.
I don't like him doing business in my place.
He was doing business in the area.
Said that was the price of doing business in Chicago.
I am doing an inn business in this town!