This keyword search functions like the search box at the top right of each page but it also provides you with the option to perform combination searches.
Clicking the plus (+) button adds another search box for immediate use in an AND search combination.
Clicking the minus (-) button on that box will exclude search returns containing that word (a combined NOT search).
Try searching for 'solid' AND 'mandala'.
Then click the - button and search again.
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