nějaký

In a sentence

• Viděl jsi nějaký film od tohoto režiséra?

  Have you seen any movie by this director?

  Here 'nějaký' functions as 'any' to inquire about the existence of an example of something.

• Potřeboval bych nějaký čas na odpočinek.

  I would need some time to rest.

  Here 'nějaký' means 'some' indicating an unspecified quantity.

• Hledám nějaký dobrý recept na večeři.

  I am looking for some good recipe for dinner.

  Here 'nějaký' serves as 'some' to mean a specific but not yet determined option.