Efficiency and sensitivity are the same thing.

Almost all typical HT speakers fall into a relatively narrow range of sensitivities, usually around 90db/watt. This is not a specification that you need to be concerned with when shopping for speakers, as it has no real impact on a typical system.

There are unusual circumstances of very high efficiency speakers like mine which are 106db/watt, but these are large horn speakers that are not at all typical. Also, there are very low efficiency speakers, but these tend to be either older deisngs from around the 1980s, or exotic types that cost a lot.

I would simply listen for speakers that sound the best to you, and not worry about this specification, since nearly all current HT speakers fall into a ballpark range that is compatible with most current amplifiers for HT use.