list flights from atlanta to boston on wednesday afternoon and thursday morning 
return flights ;return #1 from  atlanta ;return #2 to boston ;return #3 on  wednesday ;return #4 in the  afternoon ;return #3 on  thursday ;return #6 in the  morning ;return #5 ,  #7
['select', 'filter', 'filter', 'filter', 'filter', 'filter', 'filter', 'union']