[{"name":"Rice","mintemp":22,"maxtemp":32,"minrainfall":150,"maxrainfall":300,"soil":""},{"name":"Wheat","mintemp":10,"maxtemp":16,"minrainfall":75,"maxrainfall":100,"soil":""},{"name":"Millets","mintemp":27,"maxtemp":32,"minrainfall":50,"maxrainfall":100,"soil":""},{"name":"Grams","mintemp":20,"maxtemp":25,"minrainfall":40,"maxrainfall":45,"soil":""},{"name":"Sugar Cane","mintemp":21,"maxtemp":27,"minrainfall":75,"maxrainfall":150,"soil":""},{"name":"Cotton","mintemp":21,"maxtemp":30,"minrainfall":50,"maxrainfall":75,"soil":""},{"name":"Coffee","mintemp":15,"maxtemp":28,"minrainfall":150,"maxrainfall":250,"soil":""}]

db.collection.find({$or:[{mintemp:{$gte:15,$lte:20}},{maxtemp:{$gte:15,$lte:20}}]})