When searching  Library OneSearch for books on your topic, add the keyword "ill*" This searches for the abbreviations of the word illustrated, "ill" and "illus", which appear in the description line of the book's full catalog record.

Examples:

keyword = ill* medieval costume

keyword = ill* virginia woolf

keyword = ill* circus

For books which contain primarily illustrations, add to your topic keywords the phrase “pictorial works".

Examples:

keyword = pictorial works civil war

keyword = pictorial works empire state building

keyword = pictorial works flowers