Assuming the given bounding box limits are in the same spatial reference system as the stored coordinates, and you know which spatial operator (intersects or contained by) you need:
&& -- intersects, gets more rows -- CHOOSE ONLY THE
@ -- contained by, gets fewer rows -- ONE YOU NEED!
xmin, ymin, -- bounding
xmax, ymax, -- box limits
Alternatively, if you prefer the sound of "contains" (instead of "contained by") the
WHERE clause should be flipped:
WHERE ST_MakeEnvelope (...)
~ -- contains, gets same fewer rows
PS: Given (by OP after the above was posted) that the records are simple points, I think that the difference between "intersects" and "containment" becomes very subtle, affecting only the points on the edges of the bounding box.