The bust fits but the hips are too tight.
'Busto' — BUS-to. 'Fianchi' — FYAN-ki. The 'ch' is hard like 'k'.
Use this detailed feedback in the fitting room to describe a partial fit. Italian staff are trained to deal with fit issues and can often recommend alterations or a different cut.
'Busto' is the upper body or bust. 'Fianchi' (plural of 'fianco') are the hips. 'Stretto/a' means tight or narrow. Describing specific fit issues in detail helps staff find solutions — alteration, a different cut, or a different size in the same style.
Va bene in vita ma è corto.
It fits at the waist but is short.
Waist fine, length issue.
Le maniche sono troppo corte.
The sleeves are too short.
Common issue for tall customers.
È un po' lungo davanti.
It is a little long at the front.
Length issue specific to the front panel.
Italian clothing alterations ('aggiustamenti sartoriali') are widely available and reasonably priced. Letting out hips, taking in a waist, or shortening hems are standard services. Many shops have an in-house tailor ('sarto in loco').