I have come across two sentences where "да" is used where I didn't expect it. I think it must have some additional meaning?

"Да пребудет с тобой сила...." (May the Force be with you... )

"Всяк глядит, да не всяк видит" (A Russian proverb, translated to "Everything has beauty but not everyone sees it." Is it common and how is it used? [don't think this exists in English] )

Can anyone explain?