How do I search for a value in a table that is related to another table in relationship?

    const channelsWithUser = await ctx.db.query("members")
    .withIndex("by_userId", q => q.eq("userId",user._id))
    .collect(); // this has the channel id as a coloumn
    
    const allDmsThatMatch = paginator(ctx.db, schema)
    .query("directMessages")
    .withIndex("by_channelId", (q) => q.eq("channelId", /** I want to put the channelId here */))
    .order("desc")
    .paginate({numItems:10, cursor:args.searchQuery});

    const channelsWithUser = await ctx.db.query("members")
    .withIndex("by_userId", q => q.eq("userId",user._id))
    .collect(); // this has the channel id as a coloumn
    
    const allDmsThatMatch = paginator(ctx.db, schema)
    .query("directMessages")
    .withIndex("by_channelId", (q) => q.eq("channelId", /** I want to put the channelId here */))
    .order("desc")
    .paginate({numItems:10, cursor:args.searchQuery});

    const allDMsThatFit = await asyncMap(channelsWithUser, async (doc) => {
      const findDMsThatMatchInChannel = await ctx.db
        .query('directMessages')
        .withSearchIndex('search_content', (q) =>
          q
            .search('directMessageContent', args_0.searchQuery)
            .eq('directMessageChannelId', doc.directMessageChannelId),
        )
        .take(5);
      return {
        findDMsThatMatchInChannel,
        channelId: doc.directMessageChannelId,
      };
    });

    const allDMsThatFit = await asyncMap(channelsWithUser, async (doc) => {
      const findDMsThatMatchInChannel = await ctx.db
        .query('directMessages')
        .withSearchIndex('search_content', (q) =>
          q
            .search('directMessageContent', args_0.searchQuery)
            .eq('directMessageChannelId', doc.directMessageChannelId),
        )
        .take(5);
      return {
        findDMsThatMatchInChannel,
        channelId: doc.directMessageChannelId,
      };
    });