Well i managed it on my own ( only today i succeeded) with this sql.
I even had to add some more joins
thank you for the reply
SELECT main.Idnumber, `Referentie`,
`Omschrijving1`As Omschrijving, `Prijs`, `Pk`, `Type`, `Bouwjaar`, `Uren`, `Banden_voor`, `Banden_achter`,
ja_neen1.ja_neen1 As...