hygroscopicity vs solubility
Hygroscopicity is measure of how much the molecule likes to bond  molecules of water, by hydrating/covering charged part of the molecule with molecule/s of water, which relates to it having some polar or charged functional groups, like hydroxyl  group for phenols. 

Solubility is about how molecule likes to be surrounded by water, so in this case the structure of whole molecule makes a difference.
Since water is a polar solvent it likes polar solutes. If a molecule despite having one or more polar groups has, for example, a huge part which is not polar, like a carbon chain, then it will not be soluble even though it may be hygroscopic.