Hi,
Yes, you can do so by WiX code.
Using dropdown value as a trigger to search something.
Here are some reference,
//Method01,
wixData.query()
https://www.wix.com/code/reference/wix-data.WixDataQuery.html
//Method02,
dataset.setFilter()
https://www.wix.com/code/reference/wix-dataset.html#setFilter
Good luck,
Heson