Sweetie as in sweet person - Motek Sweetie as in type of sweet citrus fruit - Pomelit
trip as in voyage is nesee'ah. to trip (as in to stumble) is ma'ad.
You didn't say in which language, so I doubt I can help you with this question. In English, it is said correctly: Have a safe trip!
sweetie
Turvallista matkaa!
"Bezpiecznej podróży!"
boa viagem
nesi'ah mufla'ah (× ×¡×™×¢×” מופלאה)
khair nal jao
ασφαλές ταξίδι [asfales taxeethi]
eka suraksita yatra hai
"Želáme Vám bezpečnú cestu"