Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, hieu ve
nam thuc » nam thuoc, am thuc, nam thu
thanh di » thanh doi, thanh de, thanh do
va trien » va truyen, va thiet, va tuyen
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang x hoi. ((hieu van) OR (lieu va)) nam thuc va ((thanh di) OR (thanh pho)) va trien~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. ((hieu van) OR (lieu va)) nam thuc va ((thanh di) OR (thanh pho)) va trien".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. ((hieu van) OR (lieu va)) nam thuc va ((thanh di) OR (thanh pho)) va trien*.