Perhaps you should try some spelling variations:
vpython colisoes » vpython collisions (Expand search)
colisoes eletron » colisoes proton (Expand search)
and programming » _ programming (Expand search), goal programming (Expand search)
eletron python » eletron proton (Expand search), eletron pion (Expand search), eletron positron (Expand search)
decrease its » decreases its (Expand search), decrease with (Expand search), decrease in (Expand search)
its decrease » with decrease (Expand search), nts decreases (Expand search), to decrease (Expand search)
decrease and » decreases and (Expand search), decrease in (Expand search), decrease of (Expand search)

You may be able to get more results by adjusting your search query.

• Removing quotes may allow a broader search: (( decrease its decrease and programming ) OR ( vpython colisoes eletron python programming ))~.