Almost no sells, what to do

3 sales in 2 months with 60 assets is actually pretty decent!  

With a bit of math you can figure out how many assets you need to die a certain amount of sales.

3 sales in two months is 1.5 sales per month with 60 assets.  So if you want 15 sales per month you need 600 assets.  150 sales per month is 6000 assets.  It will vary some with the types of photos you submit.

I once ran into an account that had 19,000 photos...

See this related reply from February:

https://community.adobe.com/t5/stock-contributors-discussions/how-to-sell-stock-images/m-p/12780712#M41047

Your portfolio is a good start.  By some estimates, you need a diverse portfolio of at least 6,400 high quality assets that customers are looking for and willing to buy.  

Keep working at it. 🙂

We can often read on the net "make money by selling your photos on microstocks". OK ! The first question is: what does it mean to earn money $1? $10? $100? $1,000?. I think we have to be realistic. We are thousands every day to offer our photos. So the chances of sales are proportional. You must have at least 1,000 photos with collections to start earning some money. Do not lose hope, you can increase your chances by registering on other Stocks as well. Adobe accepts that your images be distributed to its competitors.

For 60 pictures, 3 sales is not bad at all. To make a good income, you will need to have many more pictures. And as @Ricky336 says, if your content is rare and trendy, you can make much more sales. But be assured, if you want to get rich, you need to have a portfolio of thousands of pictures and a lot of unique content.

Your portfolio doesn't have any unique subjects. To get sales, you have to upload subjects that aren't represented widely.

There are gazillions of photos on stock that have the same theme.