Gaelle, if you have 12 years of education completed I think that equivalates to US high school. Most vocational schools are 2-3 years beyond middle school (so after 8th grade). What about using the work requirement for DV eligibility? You said you were not interested in college, so I assume you got a job after high school. If you worked for at least 2 years in the last 5 years you are good to go:
"The principal diversity visa applicant must have a high school education, or its equivalent, or two years of qualifying work experience, under provisions of United States (U.S.) law.
High School Education: A high school education means successful completion of a formal course of elementary and secondary education comparable to completion of a 12-year course in the U.S.
Work Experience: If you are qualifying with work experience, you must have two years of experience in the last five years, in an occupation which, by U.S. Department of Labor definitions, requires at least two years of training or experience that is designated as Job Zone 4 or 5, classified in a Specific Vocational Preparation (SVP) rating of 7.0 or higher."
Good luck.