People on a walkway look over the rails at a man standing at edge of a canal.
People watch as a man searches for something he dropped from up above.
Just because a man is standing on the edge of a canal it does not mean he is searches for something he dropped from above. He may just be standing on the edge enjoying the view of the canal.
exists x1 x2 x3 x4 x5 x6 x7 x8.(n_rail(x4) & a_topic(x1) & of(x1,x8) & n_canal(x8) & on(x1,x2) & over(x2,x4) & at(x4,x5) & at(x5,x7) & n_edge(x7) & n_standing(x5) & of(x5,x6) & n_man(x6) & n_look(x2) & of(x2,x3) & n_walkway(x3) & n_people(x1))
exists e1 e2 s1 x1 x2 x3 x4 x5 x6.(as(e1,x3) & for(x3,x5) & from(e2,x6) & (x5 = x6) & Actor(e2,x1) & v_drop(e2) & n_male(x1) & n_thing(x5) & n_search(x3) & of(x3,x4) & n_man(x4) & Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & n_above(x2) & a_up(s1) & Theme(s1,x2) & n_people(x1))