how should we combine coverage criteria?

I was reading about coverage criteria. In this paper How Effective Are Code Coverage Criteria?

I read that the combination of statement, branch, MC/DC and loop coverage has a better result than using any of them as a single criteria (combining several control-flow coverage together is better than the strongest criterion alone).

I don't know how they combine them. anybody knows how should we combine for example two single coverage criteria? I read somewhere that they use the result of a coverage criteria to use it in another coverage criteria. but I can't find the source, therefore I am not sure either it is true or not? and also is this the meaning of combination of coverage criteria or not?