How to make a broad search in pdf-files?

I know you can search for specific words using CTRL-F or CTRL-Shift-F to search several pdf-files. But say I want to find a sentence which has two specific words; obesity and fastfood. I can search for the two words individually and try to find a sentence which contains both, but since I have many pdf files with thousands of pages this is gonna take me a very long time. How could I go about finding a sentence like this, which contains the words fast food and obesity but not in succession.

"This means that you are taking in large amount of unhealthy calories in the shape of fast food which leads to weight gain and ultimately obesity."