Sure, here are the sentences changed into reported speech:

28. "Teachers don't like noise," they said.
- They said that teachers didn't like noise.

29. "We are very calm," Tuan and Ha said.
- Tuan and Ha said that they were very calm.

30. "We don't want to watch TV," the children said.
- The children said that they didn't want to watch TV.

31. "I don't like the horror film," Charles said.
- Charles said that he didn't like the horror film.

32. "I don't like TV. I prefer cinema," Joshua said.
- Joshua said that he didn't like TV and preferred cinema.

33. "The church is just around the corner," Mrs. Robins said.
- Mrs. Robins said that the church was just around the corner.

34. "This is my favorite film," Thuy said.
- Thuy said that that was her favorite film.

35. "Sara likes to chew gum when she is at the cinema," Peter said.
- Peter said that Sara liked to chew gum when she was at the cinema.

36. "Girls prefer fashion magazines," he said.
- He said that girls preferred fashion magazines.

37. "Boys like to buy car magazines. They don't like girlish magazines," Tom said.
- Tom said that boys liked to buy car magazines and they didn't like girlish magazines.

38. "I buy this magazine every weekend," Binh said.
- Binh said that he bought that magazine every weekend.