Perhaps you should try some spelling variations:
"negative income tax" » "negativo income tax", "negativa income tax", "negativos income tax", "negative income taxi"
"negative income taxes" » "negativo income taxes", "negativa income taxes", "negativos income taxes", "negative income taxies", "negative income tales", "negative income axes"
"negative income takes" » "negativo income takes", "negativa income takes", "negativos income takes", "negative income tales", "negative income take", "negative income taken"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("negative income tax") OR ((("negative income taxes") OR ("negative income takes"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"negative income tax\") OR (((\"negative income taxes\") OR (\"negative income takes\"))))".
• Removing quotes may allow a broader search: (( negative income tax ) OR ((( negative income taxes ) OR ( negative income takes )))).
• Adding a wildcard symbol may retrieve word variants: (("negative income tax") OR ((("negative income taxes") OR ("negative income takes"))))*.