Thanks for reply. I reworked my query according to your suggestion. I think I've made something wrong. Previously report was showing some *.prt, *.drw and *.asm parts. Among them there was unassociated *.prt and *.asm files with WTparts. But report shows also *.prt associated with WTpart which name is different. For example:
Number: 123456.prt, Name: "abc" owner association with:
Number: 123456, Name: "zxc".
Another tidbit is that after added criteria for *.prt report omits previously founded *.prt which isn't associated with WTpart.
I attached my qml query.