Mike, Mike, Mike.......

Any kind of search result is limited to a certain number of threads in the results  (100 maybe?).  When you get to that limit on the results the search stops.  You have TOO MANY active threads.  It never got to the computer forum.  When you limited the search to the last 24 hours, that cut down on the number and you got there.

A PDF file does not contain words.  It is a picture.  You can not paste pictures into NAT.  Some of the word processor can convert the picture (pdf) back into text.  You had something like that going on with the second problem.  PDF files are an image file.