Perhaps you should try some spelling variations:
held world » help world, shield world, hello world
ds enabled » dis enabled, dvs enabled, ms enabled
world ds » world das, world des, world dis
ai aid » aid aid, ai aii, ai air
ai add » ai ado, pi add, ai aided

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "2008 held world ds enabled ((ai aid) OR (ai add))".
• Adding a wildcard symbol may retrieve word variants: 2008 held world ds enabled ((ai aid) OR (ai add))*.