Added this movie today: Zao Shang Xia Ban De Nu Ren (1990):
https://hkmdb.com/db/movies/images.mhtm ... ay_set=eng

The name Chen Donghai is credited in this movie and there's a guy called "小東" (that 小 is only a term like 阿), so I tagged these images:
https://hkmdb.com/db/people/images.mhtm ... ay_set=eng

But this guy has also has some resemblance with Dong Hai:
https://hkmdb.com/db/people/view.mhtml? ... ay_set=eng

Chen Donghai is also credited in "Wolf of Revenge" and one of our editors identified Dong Hai in the movie who is not credited in that way.

Chen Donghai is also credited in " Lang Zi! Bu Shi Wo", I see some resemblance with this guy, so I made some blurry screenshots (sorry, my copy is crap):

I think you are right.

I checked GUARD SOLDIER with Dong Hai appearing in a shootout and Chen Donghai is credited with F/X - added name now to the hkmdb crew list.

I also checked QUEEN OF GAMBLER (again ) with Chen Donghai listed as actor. He appears as the second thug of Chiu Ying-Hong (the other is Chang Yi-Teng).
He is in the background/in the dark in the opening shootout, but you see him better in 24 to 28 minute (VCD time) first fighting with Kara Hui and after that chasing her and after that talking with his boss.

Many Thanks Michael, for confirming and re-checking.
Also found Chen Donghai is credited for pyrotechnics in Revenge in Fury where he was already identified as actor Dong Hai.

I merged:

陳東海 Chen Donghai

Actor (5 films)

Lang Zi! Bu Shi Wo (1988)
Zao Shang Xia Ban De Nu Ren (1990)
Queen of Gambler (1991)
Wolf of Revenge (1991)
Pinoy Sunday (2010) ... Drunken scooter driver

Assistant Production Manager (1 film)

Golden Venom (1991)

Unit Manager (1 film)

Affrighted Romance (1991)

Pyrotechnics (4 films)

Queen of Gambler (1991)
Hurricane Bullet (2003)
Black Gun Discharged (2004)
Ah Sou (2005)

F/X (1 film)

Guard Soldier (2000)

With:

東海 Dong Hai

Actor (10 films)

Lover and Killer (1987)
Revenge in Fury (1989) ... [Uncredited]
Chu Ye Jia Ren (1989) ... [Uncredited]
Lady Killer (1989) ... [Extra]
Master Take Care (1990) ... [Uncredited]
Wolf of Revenge (1991) ... [Extra]
Golden Venom (1991) ... [Uncredited]
The Hooligans (1992) ... [Uncredited]
Empress Wu (1999) ... Li Chunfeng
Guard Soldier (2000) ... [Extra]

I changed the romanized main name from Pinyin to Wade-Giles. But I don't know if someone knows a movie where he is really credited with a romanized name which we could use instead? I didn't find any, but could check only a few.