IT'S straw-clutching time again. Analysts returning from home leave are now searching for a story to tell the salesmen, who want something firm, and preferably positive, to say about the Hong Kong market and its relationship to China. A few wisps that blew about yesterday could be woven together to form a rough framework of ideas. Re-exports through Hong Kong have slowed - not enough for anyone to start revising GDP figures down, or for the ''sell'' signal to go on local stocks, but enough for a slightly warier eye to be kept on all the figures which relate to China's influence onthe territory's economy. Also borne on the wind was the opinion of the State Planning Commission that consumer demand will continue to surge on the mainland. Supply will fail to meet that demand in many areas - principally food products, but also in consumer goods. This was followed by warnings from China's central bank that money supply will continue to expand quickly. The money will be used for worthy schemes - construction and the purchase of good autumn harvests. However, the end will be the same - more money in the system chasing those missing goods, and more inflation. That was yesterday's crop, and a mixed one. The good news for the honest manufacturer looking to China as a market is that the increase in retail sales of 21.6 per cent in the first half of the year is unlikely to be much slowed in the second half. Thus exports and re-exports have a possible floor. The control of money supply, however, could take on a still greater urgency. Expectations of a rapid rise will not necessarily be followed through if the State Council can rein it in. That would be at the cost of a harder landing, and some inevitable downward revisions of Hong Kong's gross domestic product this year. The prospect of urban inflation running at well over 20 per cent indefinitely cannot be attractive to the Chinese Government, already grappling with rural unrest and demands for salary increases which will only add to the problem of rising prices. None of these are straws which could threaten a broad back, and Hong Kong is not feeling too much pain from China's problems, but if they continue to pile up, the territory could begin to feel the weight.