The most common and most likely answer to this crossword clue is the 11 letter word TROUBLESOME
I've seen this crossword clue in The Times
T
R
O
U
B
L
E
S
O
M
E
More clues leading to the result TROUBLESOME
- Difficult finding Russian bread in volume
- Hiding banknotes in book is irritating
- Foreign currency hidden in volume is problematic
- Resolute mob rioting is vexatious
- Book about Putin’s cash likely to cause ructions
- To me to be without money is vexatious
- Difficult book about foreign money
- Book about Russian ready to be awkward
- Trying to procure foreign currency in great volume
- As I see it, seizing foreign currency is awkward
Buddy explains!

The straight part
We know that "Difficult" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case difficult = troublesome.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TROUBLESOME mean?
TROUBLESOME adjective- Causing trouble or anxiety