I have a borrowed piece of code that works on Google Sheets except for duplicates. The flat-file database is an index of technical articles in forty years of a monthly technical journal. On a separate sheet there is a list of "tags" which represent keywords that might be used in searches. This formula looks at three text fields in columns F, G, H - article title, article description, and core skills - compares every word to the list of tags, which is a named range called "tags", and uses TEXTJOIN to list all the "hits" - every word in the three columns that also exists on the tag list.
=TEXTJOIN(", ",TRUE,ArrayFormula(IF(ISNUMBER(SEARCH(tags,$F3369:$H3369)),tags,"")))`
But it lists every instance despite there being duplicates. Here are a few examples of the results: "cabinet parts, noises, string leveling, string leveling, tools, touchweight, touchweight, verticals" "regulating, repetition, repetition" "tuning, tuning, tuning"
I want to eliminate duplicates. Is this possible?