As with all passages of mixed bowings that combine slurs and separate notes, for example in Mozart’s violin concertos, use a short bow on the slurs and work towards each détaché or spiccato note taking almost as much bow as the slur. Each bow stroke whether two notes slurred or each one note separate uses the same 2-3 centimetres of bow.
Ševčík is specific about when to lift the bow after the 2 slurred notes, which means that almost every bow stroke starts and finishes in the air. This is a good test of the flexibility of your joints in the bow hand, especially for the 4th finger as it supports the bow in the air.
Ševčík indicates two styles, either playing loudly at the frog or softly in the middle of the bow. At the frog use a hand action and when playing in the middle use a forearm action.