Petty theft at an IHOP

My little sister works at an IHOP. Two young black adults males reached over the counter to grab my sister's phone which is also her wallet and left the restaurant. We provided officers the address where her phone GPS pinged but they stated they couldn't search the premises despite the phone turning off as soon as they arrived at the townhome building and the restaurant has surveillance of the perps faces which if they put them in a line up my my sister could ID them. Is this how cops in Houston handle things? I'm so upset for her, she's gone through a lot and this is not what she needs right now. I wish I could afford to get her a new phone but I am already assisting financially for some of her bills and other relatives. I despise the scum that steal from those less fortunate than themselves, taking what little they have in this world.