If you have lost a job description(s), instead of trying to rewrite the language, use the internet and all its resources to your advantage.

1. Check to see if your previous company has your old job posted in their career or employment section. If not, search Google by our old job title and the company name. Many times, an old job posting will show up somewhere on the cloud.
2. Search Indeed or LinkedIn for your job title. Another company usually has a similar job posting and you can "borrow" their language, and add additional responsibilities as you remember them.
3. Last, but not least, check out www.jobhero.com. They have a ton of resume samples that include job descriptions for hundreds of titles.