Extracted from [Google's search tips][1], you can enclose your individual search queries with square brackets and separating them with a `OR` or `|` operator.

`["Apple Pie"] OR ["Stack Exchange"] OR [Programming]`


  [1]: http://www.google.com/support/websearch/bin/static.py?hl=en&page=guide.cs&guide=1221265&answer=136861&rd=3