I am learning some Chengyu but after a google search with inverted commas, only a very small number of usages are found:

266 results for [霽範永存](http://dict.revised.moe.edu.tw/cgi-bin/cbdic/gsweb.cgi?ccd=xlCAxX&o=e0&sec1=1&op=sid=%22Z00000088976%22.&v=-2);

720 results for [亹亹不卷](http://dict.revised.moe.edu.tw/cgi-bin/cbdic/gsweb.cgi?o=dcbdic&searchid=Z00000161186);

817 results for [巾袖無光](http://%E5%B7%BE%E8%A2%96%E7%84%A1%E5%85%89);

886 results for [鑿枘不入](http://dict.revised.moe.edu.tw/cgi-bin/cbdic/gsweb.cgi?ccd=Bmy8xr&o=e0&brwtyp=dispcont&sec=sec1&op=v&view=114-8).

The small numbers seem to indicate most people do not use these Chengyus, and some people may not even understand them. 

Are these Chengyus considered as outdated? Do most native speakers understand these Chengyus at all?