Find the Words That Fit the Fragments

A popular puzzle is where you are given a list of word fragments and have to combine them to form a set of words such that each fragment is used only once.

For this challenge, write a function that takes a list of fragments and returns a sorted list of 20 words which can be made from them.

Example

find_words(["er", "haw", "as", "dock", "yuc", "prim", "ia", "sy", "sy", "y", "i", "thorn", "bur", "weed", "snow", "sia", "tus", "cac", "pop", "clo", "chid", "pan", "ris", "dahl", "rose", "dai", "drop", "dog", "ver", "bind", "heath", "fuch", "mine", "ca", "lil", "ter", "jas", "wood", "py", "or"])
➞ ["aster", "bindweed", "burdock", "cactus", "clover", "dahlia", "daisy", "dogwood", "fuchsia", "hawthorn", "heather", "iris", "jasmine", "lily", "orchid", "pansy", "poppy", "primrose", "snowdrop", "yucca"]

Notes

• A dictionary is required to solve this puzzle. A set of words DICTIONARY is provided in the tests - it contains all the words required (plus a few more for luck and to make the task a little more challenging).
• You always have to return a list of 20 words sorted in ascending order.
• The input fragments list will contain either 40 or 60 fragments. There are two fragments per word if the list has 40 fragments, otherwise three fragments per word.
• A word will always be just the combined fragments with no spaces or hyphens amongst them.
• Fragments are not necessarily unique within a fragments list.