.pagetypebookingslist .bookingtable tr > *:nth-child(X) {display: none;}
ExampleExamples:
.pagetypebookingslist .bookingtable tr > *:nth-child(1) {display: none;} will hide the first column which is 'Number'.
.pagetypebookingslist .bookingtable tr > *:nth-child(10) {display: none;} will hide the tenth column which is 'Email'.