Complex sentence: After unsuccessfully having tried to market the L-70 Vinka for the export market as the L-70 Miltrainer, Valmet developed a turboprop version with retractable undercarriage, which was given the designation L-80 TP Turbo Vinka.
Split into simpler sentences: After unsuccessfully having tried to market the L-70 Vinka for the export market, Valmet developed a turboprop version with retractable undercarriage. This aircraft was given the designation L-80 TP Turbo Vinka.