"Find Terms", "Search by Names", "contains" option does not return results

"Find Terms", "Search by Names", "contains" option does not return results: The "contains" option fails to work and does not appear to return any results independent of whether the interpretation of "contains" is "anywhere in the string" or "in the string but not at the head or tail."

Example searches are "breast" & "malignant."
-- Breast: returns terms for "left" and "right", but "contains" fails for "Removal of breast tissue expander"
-- Malignant: "contains" fails to find "Genetic susceptibility to malignant neoplasm of the breast