Vietnam light aircraft designs

In the 1980s the HL-1 and TL-1 light aircraft were developed in Vietnam by the Vietnam (Air Force) Institute of Science and Technology (VIST).
The HL-1 was a tandem two-seater and the TL-1 had a SBS cockpit.
Does anyone have details and data for these aircraft which had a low wing configuration and a fixed tricycle undercarriage. Engine may have been American (Lycoming or Continental).
Thank you in advance,
Wout