In variation 17 the sautillé is more complex than in variation 16. There are only two bows per note and the string crosses are faster. When the bow is only crossing strings for a short time (for instance for the two F’s at the end of bar 1) then use a pivot string-crossing action, either with the hand or the forearm, rather than a whole-arm string cross.
Pay attention also to the bow division challenges in bars 2, 4, 6 and so on. Ševčík directs the player to lift the bow in the middle, move through the air to the upper half of the bow and to use a frappé (thrown) stroke to get the bow back onto the string.
Moving the bow above the string and putting the bow back on the string in the correct position with a straight enough bow is a good exercise as it requires all the joints in the bow arm to be released and available to move when needed. Reviewing collé stroke will help check hand joints are flexible.