Search blog posts and coupons and display results in 2 different loops
I need to display the search results in 2 different loops.
Let's say, I search for "coupon" in search form on home page.
Actually, it is searching only for coupons. If nothing was found is displaying nothing was found.
I want to display results from blog if nothing was found in coupons or if found coupons display the coupons first, and, in a separate loop search for
blog posts for the same "coupon" search term.
Can somebody help, please? I'm capable to mod the theme but I don't found where.
Many thanks in advance.