Theory:

     “Did you get a chance to peek into the trunk, Seven?” I asked.

     Nishad looked disappointed. “He didn’t even ask me in,” he said. Then he smiled. “But I did find out something, Maya. I went down to the restaurant where Ramesh works and talked to him.”

     “Good for you, Mr Detective,” I said, patting him on the back, “I hope you questioned him properly.”

     Seven looked pleased. “Ramesh told me that he takes two meals for Mr Nath every morning and evening, and two cups of tea, one in the morning and one in the afternoon. Ramesh says he’s not very particular about what he eats, it’s always the same food — two chapattis, some dal and a vegetable. Mr Nath pays cash and tips well.
Explanation:
 
After Nishad had described his meeting with Mr Nath, Maya asked him if he had a chance to look at the trunk in his room.
 
Nishad, looking disappointed, informs his sister that he couldn’t get a good look at the trunk as Mr Nath never invited him inside.
 
But soon, Nishad gets excited as he smiles and reveals that he had gone downstairs to the restaurant and had a conversation with Ramesh.
 
Maya becomes thrilled and pats Nishad on his back for his 'detective-like' thought and action. She then hopes that Nishad had questioned Ramesh adequately.
 
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Ramesh worked in a restaurant

Looking pleased, Nishad starts telling Maya everything he had learned.
 
Ramesh told Nishad that he always brings Mr Nath two meals a day, one in the morning and the other in the evening. Also, he brings Mr Nath two cups of tea, one in the morning and the other one in the afternoon. Ramesh claims that Mr Nath isn't very particular about what he eats. It is always the same food: he would have about two chapattis, some dal and a vegetable. Ramesh further revealed that Mr Nath always pays in cash and, to Ramesh's delight, tips him generously.
 
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Mr Nath took the same food everyday
 
From Ramesh's account of Mr Nath, it could be understood that Mr Nath is unlikely to be poor, as he claims that he pays him in cash and also tips him well. Had he been poor, he wouldn't have tipped him "well", nor would he have paid cash all the time. On the other hand, he has only two meals a day.  So, why did he do that? Could itbe because he wasn't financially well off? Or, could it be because he was unwell and, as a result, had a general lack of appetite? Or was it a part of the diet prescribed by his doctors?
 
Though the lesson doesn't answer these questions, it is highly imperative for the readers to ponder over such questions to get a better understanding of Mr Nath. 
 
The paragraphs are important not only because it reveals more about Mr Nath, but also because it further explores the relationship between Maya and Nishad. Apart from the differences in ideas and perspectives (between the siblings) that we had previously seen, the paragraphs show us the friendly relationship between them. For instance, Nishad is happier to please his sister and is excited when he gets a 'pat' from her. On the other hand, Maya is encouraging and genuinely happy when she realised that Nishad had collected some crucial information for their investigation. Hence, it is evident that the siblings have no rivalry, jealousy, or ill feelings between them.
 
Meanings of difficult words from the paragraphs:
  
Sl. No.
Words
Meanings
1
PeekA quick or secretive look
2
PatTo touch quickly and gently with the flat of the hand
Reference:
National Council of Educational Research and Training (2007). Honeycomb. Expert Detectives:Sharada Dwivedi (pp. 126-132). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.