Flexofytol PLUS® contains 72 mg of curcumin, does it mean that it is more dosed than Flexofytol® which contains only 42 mg of curcumin ?

No because it is the amount of assimilable curcumin (= bioavailable) that matters.
The bioavailability is equal for the 2 forms, which means that in terms of curcumin take a Flexofytol^® capsule is equivalent to taking a tablet of Flexofytol PLUS^®.