query: SELECT TYPE FROM ship WHERE flag  =  'Panama' INTERSECT SELECT TYPE FROM ship WHERE flag  =  'Malta'
question: What-all types ships have both ships have Panama Flags and Malta flags?
query_toks: SELECT TYPE FROM ship WHERE flag = 'Panama ' INTERSECT SELECT TYPE FROM ship WHERE flag = 'Malta '
query_toks_no_value: select type from ship where flag = value intersect select type from ship where flag = value
question_toks: What-all types ships have both ships have Panama Flags and Malta flags?