Solutions :

3-letter words (1 point): 33

CIG; DIE; DIS; DZO; ERS; EXO; GET; GIE; ICE; IDS; IOS; IRE; ORE; ORS; QIS; REC; REG; REI; RET; REX; RIG; SEG; SEI; SET; SIX; SOX; SRI; TEC; TEG; TES; TEX; XIS; ZOS.

4-letter words (1 point): 19

CERO; CETE; CIRE; DIES; DIET; DIXI; DZOS; ERIC; EROS; GIRO; ICER; OXER; OXID; REIS; RETE; RICE; SORE; SORI; ZORI.

5-letter words (2 points): 12

CEROS; CETES; DIXIE; EXIES; GIROS; ICERS; OXERS; OXIDS; RETES; SIXER; SOREX; XERIC.

6-letter words (3 points): 4

DIETER; OREXIS; SEIZOR; SIXERS.

7-letter words (7 points): 3

CIRSOID; DIETERS; SEIZORS.