Let's start with your example. Part of what would make it sound "wrong" to add "the" to any one of the things you list is that it would break parallel structure unless you added it to all of them. Though this is a mistake that native speakers make frequently, it is not good style to say:
My shopping cart includes vegetables, meat, the cookie, and ice cream.
because "the cookie" breaks parallel structure. I could instead say:
My shopping cart includes the carrot, the beef, the cookie, and the ice cream I needed.
A notable exception to this is that "the" can be used on the first item only, though it is implied that it applies to the others as well as in:
The Declaration, Constitution, and Bill of Rights are all stored in the National Archives in Washington DC
Where "the" is implied before "Constitution" and "Bill of Rights".
As for when to use "the" versus when not to, "the" is used to denote one and only one of something. For example, if you were to say:
the increase in foreign investment
you are talking about a specific increase. It might sound more natural if you provide additional context, like saying:
the increase in foreign investment that resulted from globalization.
or something similar. When you omit "the", you are no longer referring to one and only one of something, typically you are instead referring to something in general. You can say:
Housing markets benefit from factors including high demand and increase in foreign investment.
To talk about housing markets in general. High demand here is not referring to any particular period of high demand, just high demand in general. If I say:
The housing market in the United States benefited from the high demand due to the GI Bill, and the increase in foreign investment brought by expatriation from Europe.
It is clear that I am talking about particulars.
