how do you know which spices have jwh 018?

[Nanosage]

I am really liking the whole k2 and legal blends thing. But now k2 specifically is illegal here, what other spices even have jwh 018? I haven't tried any of the others. But if you guys could share which synthetics you like most and tell me? And I am buying it from a headshop, not online.. Just, how do I figure which ones have jwh 018 while I am in there? I mean if I just ask which incenses contain 018, wouldn't that be a bit sketchy?