Would something like Click to Sort help?
Also check out the last couple of TechHelp videos:
Sort by Month
Sort Multiple

after sorting it ,  same dates appear many times. It is a bit confusing. I just want same dates appears only once cos it is easier to read.

Unfortunately, on a form, there isn't a way I'm aware of to group the dates.  The best you can do is the sorting.

You can accomplish Grouping like you are talking about in a report but that is meant for printing out.

A workaround would be a Combo Box with your dates and a List Box with the other data you want to display. Use the After Update event to filter the List based on the date selected in the Combo Box. Perhaps even more confusing for some than what you have now.

can it be done in conditional formating? lets say when I select a product , other products with same date appear same color

I've actually got a video on something very similar coming out soon. Hang tight.

thanks, wish I will not miss it