We are so happy you brought this to our attention. There was an error in the way the sizes of our garments were showing. The sizing has been updated. If you take look now you should see a larger range of sizes
There really isn't a better size chart but since these are sold and sized by waist and inseam measurements. Your best bet is to have people measure if they don't know. Here are the guidelines from Dickies on how measure: For the most accurate results, measure yourself in your undergarments. Give all measurements in inches. If your measurements are between sizes, order the larger size. For greatest accuracy, have someone take your measurements rather than yourself. The tape measure should be pulled snug, not tight. Check the size scale of all garments being ordered to ensure that all measurements were taken at the proper points. Chest: Measurement is taken at the fullest point of the bust. Measure across shoulder blades with arms relaxed down at sides, keeping tape parallel to the floor. Hold tape level and firmly but not tight. Waist: Measure around your natural waistline. Keep the measuring tape comfortably loose. Hip:Measurement is taken by standing with heels together. Keep tape straight and parallel to the floor, measure around the fullest part. Inseam: Measure a similar pant that fits you well. Measure along the inseam, from the crotch seam to the bottom of the hem.