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The following information needs to be modified due to more specific explanation of Intermolecular Forces (IMF).
van der Waals forces is the name people give to both dipole-dipole IMF (D - D), between two polar molecules, and London dispersion forces (LDF), between 2 non-polar molecules.
Therefore, Hydrogen bonding (H - B) is not considered a van der Waal force because Hydrogen bonding IMF is larger (or stronger) IMF than van der Waals forces. Remember, H - B is the special vary large dipole - dipole IMF caused when by dipoles that contain H - F bond, H - O bond and/or H - N bond since these bonds have high Δ EN (electronegativity difference) but more importantly the non-hydrogen are small radii atoms (causing higher Coulombic force).
With respect to London dispersion forces (LDF), actually all compounds and <b>even single atoms have LDF. Remember, LDF is caused by the fact that the electrons in atoms and/or molecules are in constant motion so there is always times where electrons are not equally distributed over the element and/or compound causing an Instantaneous dipole (unevenly distribution causes a partial negative and partial positive area of the species making instantaneous Coulombic forces). This instantaneous Coulombic forces only exist of a short period of time (billionth of a second)if you