The isoscalar s-waves of the pi pi scattering (from the threshold up to 1.9
GeV) and of the pi pi --> K (K) over bar process (from the threshold to si
milar to 1.46 GeV) are analyzed simultaneously in the model-independent app
roach. A confirmation of the sigma -meson at similar to 665 MeV and an indi
cation for the glueball nature of the f(o)(1500) state are obtained. It is
shown that the large pi-pi -background, usually obtained, combines, in real
ity, the influence of the left-hand branchpoint and the contribution of a w
ide resonance at similar to 665 MeV. A minimum scenario of the simultaneous
description of the processes pi pi --> pi pi, K (K) over bar does wihtout
the f(o)(1370) resonance. A version including this state is also considered
. In this case the f(o)(1370) resonance has the dominant s (s) over bar com
ponent (the ratio of its coupling constant with the pi pi channel to the on
e with the K (K) over bar channel is 0.12). The coupling constants of the o
bserved states with the pi pi and K (K) over bar systems and the pi pi and
K (K) over bar scattering lengths are obtained.