"Iron shoes can't be found anywhere, and they can be obtained easily" means: when I was looking for them, I couldn't find them because they were worn out, but I didn't expect to find them easily later; It is a metaphor that what is urgently needed took a lot of effort to find, but it was inadvertently obtained.
Pinyin: tàpòtiéwúmíchú, dé lá i quá n bú f è i g not ng f?
Source: Meng Long's "Jing Shi Jin Mei Maid Appreciates the Show Child": "Shut the door, the two talked in detail. Exactly: iron shoes are nowhere to be found, and they are effortless! "