The first one is not a sandpiper, it is a stint.
you can check The Birds of Hong Kong and South China p. 104
The second one are wood sandpipers. Author: ajohn Time: 20/04/2009 11:14
The birds in the first photo are Long-toed Stint. Note the very small size, pale legs and bright, orange-toned upperparts Author: wchiyin Time: 20/04/2009 11:52
thanks a lot
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