How did the elderly woman know that Mita and others want to buy food? (Read the text and answer the question)

The local people were buying and selling goods at the Tha Kha floating market.

The food was served in bowl made from banana leaf.

The Tha Kha is a traditional floating market in Thailand.

The Thai people do not understand English or an other language excepting their mother tongue. They communicated with Mita and Zara in their own way of communication.

The ingredients of the food 'Pad Thai' are noodles, shrimps, tomato and some vegetables with freshly roasted crushed peanut.

The Tha Kha natives are the customers of the floating market.