I am seeking a job in technical writing, what should I include in my portfolio to attract employers?

Your experience, courses you have have completed, along with some illustrations of the deliverables you've produced.

I would mention my strong capabilities in writing chemistry experimental reports /  draft of my dissertation

Previous experience in the field being applied for.

training certification for say S1000D for aviation.

because many Industries want to be write that type some technical

The books that I've already and published in France

You must include your samples which would show your ability to do technical writing. Besides, the companies your worked for or the projects you worked on must be highlighted in your portfolio. Moreover, your education and the certifcations you acquired must also be clear in your portfolio.

The most important thing is samples of your work and the tools you can work with. Ability to develop computer-based training and visuals is a great advantage.

Your education, experience, motivation and examples of work.  For examples don't forget illustrations and drawings as well.  Knowledge of tools, like software, and knowledge of any industry or area is excellent, such as manufacturing, quality, chemistry or science, engineering or coding.

All you need about the availability of technical writing and genres

Depends on what kind of a job you are applying for. If you are applying for a job where your focus is going to be software documentation, then you would want to include samples of those types of documents. If you are applying for a job where your job major responsibility would be writing grants, then you want to include documents that reflect your grant-writing skills.

State your previous work; in terms of the domains/industries you have worked on, and the deliverables you produced in each of these domains.