A receiving method, a sending method, a terminal, and a network side device are provided. In the sending method, when sending to the terminal the physical downlink control channel PDCCH in the search space associated with the CORESET, the network side device performs frequency-domain offset processing on the CORESET and search spaces corresponding to different times or search spaces in the CORESET at a same time in a plurality of manners, to improve timeliness of PDCCH sending.