The most common and most likely answer to this crossword clue is the 4 plus 7 plus 2 plus 5 letter word LIKE NOTHING ON EARTH
I've seen this crossword clue in The Times
L
I
K
E
N
O
T
H
I
N
G
O
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E
A
R
T
H
Buddy explains!
The straight part
We know that "Very strange" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case very strange = like nothing on earth.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.