0 something that is impossible or extremely difficult to find, especially because the area you have to search is too large:
Without prior knowledge of changes in specific hormone or hormone receptor levels, however, a candidate gene approach resembles an attempt to find a needle in a haystack.
It was a bigger problem than finding a needle in a haystack.
The latter can become a needle in a haystack.
It is like looking for a needle in a haystack.
I know that that can be rather like looking for a needle in a haystack.
Trying to use such records to trace stolen goods will be like trying to find a needle in a haystack.
Any form of static check unrelated to good intelligence is like looking for a needle in a haystack.
Tracking down cyber-crooks is like looking for a needle in a haystack.
