The following information was taken from HathiTrust Help.
Primary Catalog Search:
- Phrase Searching: Use quotes to search an exact phrase: e.g., "occult fiction"
- Wildcards: Use * or ? to search for alternate forms of a word. Use * to stand for several characters, and ? for a single character: e.g., optim* will find optimal, optimize or optimum; wom?n will find woman and women.
- Boolean Searching: Use AND and OR between words to combine them with Boolean logic: e.g., (heart OR cardiac) AND surgery will find items about heart surgery or cardiac surgery.
Full-text Search:
- Phrase Searching: Use quotes to search an exact phrase: e.g., "occult fiction"
- Multiple Term Searching: When your search terms are not quoted phrases, avoid common words (such as: 'a', 'and', 'of', 'the', etc.) to speed up your search.
- Boolean Searching: Use AND and OR between words to combine them with Boolean logic: e.g., heart OR cardiac will find items containing the word heart or the word cardiac; heart AND cardiac will find items containing both words. Use a minus (-) to remove words from the result e.g., heart -cardiac will find items containing the word heart that do not include the word cardiac.