Get Words Containing These Letters, At Minimum Word Search Tool, using the censored Enable word list
The "contains minimally" live dictionary search finds words that contain, at minimum, all of the letters specified, and then some, in any order. For example, if you request the following: iiiiiz, the resultant words will have at least 5 i's, and a z (e.g. individualization initialization). If you want to see more words in the results, use the mammoth censored word list.
Sort the results by length to find words that are very close to, or slightly longer than, your requested letters.