SCTR more than 80 for 2 weeks

It's counter-intuitive, but you want to test for the minimum sctr greater than 80.

The function for working with a minimum value over some period of time is min( ), and you can pick the value you want from the Price, Volume and SCTRs drop down on the scan builder page. There are a lot of SCTR sub-types. So you could use

and [min(10, SCTR) > 80]

or, in place of SCTR, you could use any other sctr.xxx on the drop down list.