query: SELECT TYPE FROM ship WHERE flag  =  'Panama' INTERSECT SELECT TYPE FROM ship WHERE flag  =  'Malta'
question: Find the ship type that are used by both ships with Panama 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: Find the ship type that are used by both ships with Panama and Malta flags.