All it means is that you had multiple bidders on each of your items. As a result, you have the option to offer a second chance offer on each item to the second to highest bidders (or third to highest, etc.). So for example, if one of your buyers doesn't pay (I know you said above they did, but just as an example), or if they pay, receive the item and change their mind about it, or if you run into a difficulty with one of your buyers, etc. you have the option to offer your item to those "second in line" without having to relist and go through the bidding process all over again.
It's an automatic thing that shows up on ebay when you have multiple bidders and, of course, you don't have to take advantage of it. I think the option is available for 30 days following the close of an auction but don't quote me on that.
Hope this makes sense?