Short guy stealing black and silver drinks products (3,4)
I believe the answer is:
tea bags
'drinks products' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'short guy stealing black and silver' is the wordplay.
'short guy' becomes 'teas' (I can't justify this - if you can you should give a lot more credence to this answer).
'stealing' indicates putting letters inside.
'black' becomes 'b' (as in pencil classifications).
'and' means one lot of letters go next to another.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'b'+'ag'='bag'
'teas' enclosing 'bag' is 'TEA-BAGS'.
Can you help me to learn more?
(Other definitions for tea bags that I've seen before include "They hold leaves for infusions" , "those in hot water?" .)