So we know the concept of dipole moment that it is depends on the charge and distance between central atom and side atoms

But the charge is more prominent then distance

It is determining as polar and non polar molecules

It is used for covalent or ionic molecule

${\mathrm{\mu }}_{\mathrm{net}} = 0$ It is for non polar molecule

${\mathrm{\mu }}_{\mathrm{net}} \ne 0$ it is for polar molecule

So from above theory we conclude that

So in above hydro quinone molecule the $-\mathrm{OH}$ molecule are in the position of right side that's why it's dipole moment is not be equal to zero 

Also it is happend in the case of ipso-parathiophenone