Use commas between search words. The search words will be used to search Titles, Content, and the Category or Tag names. See the Categories and Tags for those names.
Search for any of the keywords across all posts
For example: “personal, thinking” will match posts with the categories personal-level or critical-thinking (quotes are not included for this example). If you have a phrase or multiple words that need to be matched exactly, then put quotes (“) around them. For example: “Ad Fontes”
Search for posts that have all the keywords
For example: “societal, fascism” matches posts with the tags societal-level and fascism.