Keyword searching is the most common search strategy when doing research; when doing research about First Nations Peoples, it's important to recognize the many ways -- past and present -- writers describe topics, issues, and groups of people. A simple keyword search for 'Indian' may pull up some older records referring to American Indians, but most of the results would probably be related to peoples from India. Keep in mind the following variety of terms:
This gets even more granular when we're looking at a particular group of people such as a tribe or clan. For example, Ojibwa has different spelling variations depending on location and linguistic dialect. You also have to consider that indexes may use the anglicized version of a tribe versus the preferred name of a people or tribe; for instance, Chippewa is the anglacized name for the Anishinaabe people.