I did a bit of a combined Google and eBay (!) search, and I believe the set is called Friends are Flowers. There seems to be a few stamps in your box that may come from a different set, and you may be missing some stamps from Friends are Flowers, including a sentiment that says: Friends are flowers in the garden of life. Here is the only image I found, online, that shows the set. The eBay set may or may not be complete; quite often, the older the set, the more chance that stamps have been switched out:
Friends are Flowers eBay listing.