Asian kids sitting on a mat playing with a toy.
Kids are playing with footballs and toy trucks.
There are many other toys besides footballs and toy trucks.  The first sentence states toy, which is singular, while footballs and toy trucks are plural.
exists e1 s1 x1 x2 x3 x4 x5.(a_topic(x1) & with(e1,x5) & n_toy(x5) & on(e1,x3) & n_playing(x3) & of(x3,x4) & n_mat(x4) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_kid(x1) & a_asian(s1) & Theme(s1,x1))
exists e1 x1 x2 x3 x4 x5.(with(e1,x2) & n_truck(x4) & of(x4,x5) & n_toy(x5) & n_football(x3) & subset_of(x4,x2) & subset_of(x3,x2) & Actor(e1,x1) & v_play(e1) & n_kid(x1))