spsitedataquery return incorrect result if multiple list id of different types are queried.

query  property:

"<OrderBy><FieldRef Name=\"Modified\" Ascending=\"FALSE\" /></OrderBy><Where><And><Lt><FieldRef Name='Created'/><Value IncludeTimeValue='TRUE' Type='DateTime'>2019-05-04T16:04:00Z</Value></Lt><Or><IsNotNull><FieldRef Name=\"WeChatPicUrl\" Nullable=\"TRUE\"/></IsNotNull><BeginsWith ><FieldRef Name = \"ContentTypeId\" /><Value Type = \"ContentTypeId\" >0x012002</Value></BeginsWith></Or></And></Where>"

lists property:

"<Lists><List ID = '48c04208-2577-4d6f-b613-d8a374e4d6ef' /><List ID = '2d43e76b-58fc-4587-8ad9-69b6092d17ec'/></Lists>"

One of the list is a discussion board  and the other is an image library.

                        query.ViewFields = @"<FieldRef Name=""Author"" Nullable=""TRUE"" /><FieldRef Name=""ItemChildCount"" Nullable=""TRUE"" /><FieldRef Name=""Modified""/><FieldRef Name=""Title"" Nullable=""TRUE"" />";
                        query.ViewFields += @"<FieldRef Name=""WeChatPicUrl"" Nullable=""TRUE""/>";
                        query.RowLimit = 5;

It only returns listitem from the image library, no item from the  discussion board list returned. 

If I change the lists property to  include only one list, returned results is correct.