The invention relates to thermoplastic molding compositions comprising A) from 10 to 89% by weight of a polyamide, B) from 10 to 60% by weight of a fibrous reinforcing material with fiber length from 3 to 24 mm, C) from 1 to 20% by weight of at least one polyolefin composed of ethylene or propylene or a mixture of these, where polar functional groups are excluded, D) from 0 to 5% by weight of at least one nanoparticulate oxide or oxide hydrate, or a mixture of these, of at least one metal or semimetal, with a number-average primary-particle diameter of from 0.5 to 50 nm, and with a hydrophobic particle surface, and E) from 0 to 40% by weight of further additives, where the entirety of components A) to E) gives 100%.