The thing is higher dimensional needles are already supported:

```
>>> np.__version__
'1.8.0'
>>> a = np.arange(5)
>>> b = [[1, 2], [3, 4]]
>>> a.searchsorted(b)
array([[1, 2],
       [3, 4]], dtype=int64)
```

Andthe way it is implemented, this feature requires that the needle be contiguous.