China Coal - Hunan Pugi Geological Exploration - PQWT M 100 review: underground water detector pqwt m100 - no accuracy before 40 m deep

I bought to Chinese company CHINA COAL Hunan Pugi Geological exploration via ALIBABA a water detector PQWT M100
Here is strict explanation of all the trade, just to inform peoples.
I processed with Alibaba Trade thinking "as they say" that will protect my transaction.
I inquired for a device fitting to my specific requirements: Accuracy needed from 0 meter to 20 meters deep.
We are in a calcareous island, see water infiltrate in ground under 20meters. so noway to have natural water under this depth or very deep and but is not same work.
- China Coal replied to my inquiry and offer its product PQWT M100, with a lot of explanation and presentation of analysis done.
- Commercial and technical services were perfect, available and friendly.
- Transaction went well and I received my product on time.
Problems began there:
- No user's book for the use of this device !
- No information about an application to load directly from supplier which need full access to your cellphone without restriction to work. If not your device cannot work.
- Question to China Coal: You didn't inform before the sale that your device need a full access to cellphone?
Reply of the supplier China Coal: we don't steal information in your device !
- Question to China Coal: Why do you need full access even if your App asks only access to Location ?
Reply of the supplier China Coal: we don't steal information in your device ! Maybe the only sentence they know in English !
After to have lost 2 days to talk with commercial and technical services, I obtained a real user's book for their device. Big surprise, when a commercial or the presentation of device in Alibaba announce 5 second to do one measurement, reality was more than 2 minutes by measurement and you need at least 30 measurement before to obtain a realistic image of underground. Following all requirements and step for each measurement, you need more than 2.30 hours to obtain picture of a land of 10 meters by 3 meters so 30 Sqm !
- Question to China Coal: Your device doesn't fit technical data you gave before the sale ?
Reply of China Coal: You had to inquired more before to buy, that is only your mistake ! Final reply
Now we go to the work of this device, and we processed strictly as per user's book says. Result of work after 4 different survey in different places.
First survey doesn't indicate any maters for the 20 first meters of underground ! good image after 40 meters deep
Second survey doesn't indicate an active deep well (10 cubic meters per hour and 15 meters deep) good image after 40 meters deep
Third survey no matters shown in 30 first meters even if a cave in rock is accessible at 12 meter deep going till 50 meters deep, after good image
Fourth survey little light matter shown under 6 meters, but a well is drilling in hard rocks until 18 meters deep and not seen good image under 40m.
Of course we filed a dispute with help of Alibaba Trade, presenting all evidences of the 4 surveys, our specific requirements for the depth of 0 to 40meters, recognition of this requirements by China Coal, recognition of their technical services that they don't have accuracy in this depth required.
Reply of China Coal: they reply only in Chinese, so we never know what they said !
Alibaba only replied to us : We don't have enough evidence !
But what kind of evidence do you want ? you have my inquiry specified 0 to 40 meter deep, you have confirmation from China Coal telling our device can do that, before the sale. In front we present other text from technician which said after sale "device cannot do that, low accuracy in first 20 meters" we present proof of no information over 4 surveys for the depth specified. What more you want.
Second reply from ALibaba: Alibaba need an official expertise to make decision, buyer has to pay for that $600, (price of the device) ! Fees non refundable, but if proved guilty supplier will be only sanctioned by Alibaba, but not oblige to refund the device !
Of course we let fall the dispute to don't lost more money !

So for this case, Alibaba Trade just cover the bad supplier who shoulder their profit, do not hope their help when it comes to fight big companies, they just force you to give up for the case and shoulder bad supplier.
But to be honest, in a previous case with a smaller supplier, Alibaba Trade shouldered us and we obtain a refund for bad materials received, So thanks for that case Alibaba Trade, it will be nice if you act fairly always and not sometimes by interest...

BE AWARE THAT CHINA COAL IS REALLY A DISHONEST COMPANY AND JUST HIDE BEHIND CHINESE LAW TO CHEAT AND STEAL FOREIGN CUSTOMERS.