Cannot search from child record columns

Expected behavior Table containing following dataset can search based on fields key1- key7 should also be able to search based on child records. Actual behavior Table containing following dataset can search based on fields key1- key7 but not on key9-key16 (using searchLocalDataByMultipleFields()) Resources (screenshots, code snippets etc.) { "results":[{ "key1" : "1244", "key2" : "1234567", "key3" : "Invoice", "key4" : "98765425", "key5" : "ZXYC", "key6" : "15/DEC/2020", "key7" : "20201215", "key8" : { "results" : [ { "key9" : "1244", "key10" : "1234567", "key11" : "Note", "key12" : "98765424", "key13" : "ABCD", "key14" : "15/DEC/2020", "key15" : "20201215", "key16" : "0.00 " } ] } }, { "key1" : "1244", "key2" : "1234567", "key3" : "Invoice", "key4" : "98765425", "key5" : "ZXYC", "key6" : "15/DEC/2020", "key7" : "20201215", "key8" : { "results" : [ { "key9" : "1244", "key10" : "1234567", "key11" : "Note", "key12" : "98765424", "key13" : "ABCD", "key14" : "15/DEC/2020", "key15" : "20201215", "key16" : "0.00 " } ] } } ] }