How IPFS finds nodes through DHT

When I publish a new file to IPFS network with my node, only my node owns a copy of this file. How do other nodes find this file on my node?
I read the IPFS white paper. IPFS should use KADEMLIA DHT, so according to my understanding, the block should be stored on the corresponding node according to the hash value, So that other nodes can quickly find the node that stores the data.
But from the current analysis, the blocks are not actively backed up to the corresponding nodes. Feeling incompatible with the design of KAD.