Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
doc sach » hoc sach, toc sach, nuoc sach
thuoc va » thuc va, thuoc ma, thuong va
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
huu tre » huu tri, cuu tre, huu them
va dan » ca dan, va dao, va dau
dan va » doan va, dan ca, ban va
va huu » vu huu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky nang xa hoi. ((hieu va) OR (lieu va)) nam thuoc va dan va huu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ky nang xa hoi. ((hieu va) OR (lieu va)) nam thuoc va dan va huu tre".
• Adding a wildcard symbol may retrieve word variants: doc sach ky nang xa hoi. ((hieu va) OR (lieu va)) nam thuoc va dan va huu tre*.