A Google R&D post from a few months ago A new flavor of Google Trends interpreted the Google trends graphs for vanilla ice cream and chocolate ice cream.
I commented about the post here: Does Google Trends data equate to consumer interest?
Taking another look at the Google R&D post, an additional problem is the queries the R&D poster uses are imprecise for a conclusion about ice cream.
My suggestion: Try these instead: "vanilla ice cream" and "chocolate ice cream".
Probably, there are far more chocolate products in the world than vanilla. For example: cakes, candy bars, cookies. However, folks still like vanilla ice cream more than chocolate ice cream.
The surrounding quotes enable Google Trends to return ice cream rather than a mixture of products.