Continuing with using homelessness as an example, provided below are the Library database and search strategies to assist you in researching advocacy issues and your policies. Keep in mind that the Advanced Search link can help modify and narrow your search.
homeless* AND "advocacy group*"
homeless* AND (voucher* OR subsid*) AND advocacy
homeless* AND "political action"
homeless* AND "social action"
homeless* AND advocacy AND (challenge OR opposition)
homeless* AND characteristics
homeless* AND "risk factors"
homeless* AND "socioeconomic factors"
homeless* AND (issue OR concern OR consideration)
homeless* AND "social policy" AND (histor* OR trend)
homeless* AND "economic policy" AND (histor* OR trend)
homeless* AND "political policy" AND (histor* OR trend)