To search for opportunities based on multiple criteria, simply key into the address bar: http://sav-opp.blogspot.sg/search/label/Criteria1+Criteria2 etc.
Simply replace "Criteria1", "Criteria2" with the criteria in Title Case. You can search by beneficiary group, location, commitment level and/or assignment type.
For example, visit http://sav-opp.blogspot.sg/search/label/Children+Regular+East for volunteering opportunities with children on regular basis in the East.\
You can refer to the labels on the top to see what is available.