Running a search query I only find one episode whereas I know there are three available on the iPlayer?  What’s the reason the search doesn’t find these other episodes?

You've not exactly given much to go on there.

What query are you running? What programme are you talking about (provide a link to the iPlayer listing).

Fair comment.

get-iplayer —type=tv snowfall

This query returns 2 (2147,2148) episodes where if you look on iplayer via web there are 10 episodes available.

Another alternative, get-iplayer —type=tv mears

This query returns 1 episode (1061), where there are 3 episodes online.

Read the FAQ list section on searching

(13-12-2017, 11:10 PM)Fair comment.

get-iplayer —type=tv snowfall

This query returns 2 (2147,2148) episodes where if you look on iplayer via web there are 10 episodes available.

I see 5 when i use web pvr , BUT , a quick check of the webpage shows 10.
It also states '' Download not available.'' beside each episode , you can only watch via the webpage not download.
I assume that therefore blocks get_iplayer from downloading too.

On the series page for Snowfall it has

Can Snowfall be downloaded on BBC iPlayer?

This series can only be streamed on BBC iPlayer. We always aim to let users download programmes so they can be watched offline; however for a number of reasons including technical problems, legal or contractual issues this isn’t always possible.

(14-12-2017, 02:55 PM)It also states '' Download not available.'' beside each episode , you can only watch via the webpage not download.
I assume that therefore blocks get_iplayer from downloading too.

No. I refer you to my previous post.