Solutions :

3-letter words (1 point): 64

ADD; AHI; AHS; ARD; ARE; ARF; ARS; AWE; DAD; DAH; DAW; DUE; DUH; EHS; ERA; ERF; ERS; FAD; FAH; FAR; FAT; FAW; FEH; FER; FEW; FIE; FRA; HAD; HAT; HAW; HER; HES; HEW; HIE; HIS; HUE; ISH; RAD; RAH; RAT; RAW; RED; REF; REH; REI; REW; RUD; RUE; SEI; SHA; SHE; SIF; SUD; SUE; SUR; TAD; TAR; TAW; URD; URE; USE; WAD; WAR; WAT.

4-letter words (1 point): 64

AHIS; ARED; ARSE; DAHS; DARE; DAWD; DEUS; DRAD; DRAT; DRAW; DURA; DURE; DUSH; EISH; FADE; FAHS; FARD; FARE; FARS; FEHS; FEIS; FIER; FISH; FRAT; HADE; HARD; HARE; HIES; HUED; HUER; RADE; RAHS; REDD; REHS; REIF; REIS; RHUS; RUDD; RUDE; RUED; RUSE; RUSH; SEIF; SHAD; SHAT; SHAW; SHEW; SUDD; SUED; SUER; SURA; SURD; SURE; SURF; TAHR; TARE; TARS; URDE; WADD; WADE; WADT; WARD; WARE; WARS.

5-letter words (2 points): 35

ADDER; ADRED; AREDD; ARUHE; DARED; DERAT; DRUSE; DWARF; FADER; FARED; FARSE; FRUSH; HARED; HUERS; RAWER; REUSE; RHIES; SHADE; SHARD; SHARE; SHIER; SHRED; SHURA; SURAH; SURAT; SURED; TAHRS; TARED; TARSI; TAWER; USHER; WADER; WAFER; WARED; WEISE.

6-letter words (3 points): 15

ADDERS; ARSIER; DRAWER; FADERS; FADEUR; FISHER; HEIFER; REWARD; RUSHER; SHADER; SHARED; SURFER; SURFIE; WADDER; WADERS.

7-letter words (7 points): 7

DRUSIER; DWARFER; FADEURS; RUSHIER; SURFIER; TARSIER; WADDERS.

8-letter word (11 points): 1

DWARFISH.