How to say "但是我使用此术法" (dàn shì wǒ shǐ yòng cǐ shù fǎ) in Chinese dialogue

dànshìshǐ使yòngshù

But it only works on

Idioms & Colloquial Expressions
Grammar Patterns
INTERACTIVE SCRIPT TIMELINE
LINE 0137:17
bié
fāng
biàn便

It's very convenient.

LINE 0237:19
PLAYING SCENE
dàn
shì
shǐ使
yòng
shù

But it only works on

LINE 0337:21
zhǐ
duì
zhū
jiān
shī
wēn
yǒu
xiào
a

Zhu Dajian and Shi Wen when I use it.

Show Information
Source MediaTV Series
Season & EpisodeS1 E18
Timestamp37:19
TMDB ID272715