We know that Google does not use meta keywords for ranking, but does it search for potential keywords in meta descriptions?
The last time I tested this, it does not. If you put some weird word in the meta description (something like "xenylotior"), then you will not be able to find it in Google search. If you put that word in the text of the page, you will be able to find it. Words in the meta description are not used for ranking because they are not indexed and not searchable.
Words in the meta description do get bolded when they are shown in the SERPs when they match the query. If the meta-description does not contain the words in the query, Google is much more likely to choose another sentence from the text rather than the meta description. So it is still important to put your keywords into meta description in a way that will make your listing in the SERPs attractive to your users.