If you were using Multi-Point AF, try Flexible Spot AF or Monitoring AF instead. Looks like your camera supports 3 modes of auto focus. Mulit-Point would make the choice of what is focused for you, Flexible Spot allows you to decide where the focus point should be in the picture. Monitoring would be good for focusing on something that may be moving, squirmy kids, pets, etc where you may need to track movement before taking the photo.
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