How to search based on custom properties using TREX

Hi, i have installed TREX and able to create indexes and do basic searching. i have created some custom resurce types in sys admin->sys.config->cm->global services->resource types. i have created some properties in property meta data for these types. i made these properties indexable. but how can i search based on these properties using trex? can anybody know how to do this? please help me. thanks in advance..

thanks & regards

kranthi