Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
doc sach » toc sach, nuoc sach, dac sac
thuoc va » thuc va, thuoc ma, thuong va
hoc sach » hoc sinh, hoc cac, hoc anh
hieu va » hieu qua
cuu tre » cua tre, cau tren, cau treo
nang xa » nang x, lang xa, nang ma
va dan » ca dan, va dao, va dau
dan va » doan va, dan ca, ban va
va cuu » va cau, va chu, va 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) OR (hoc sach)) ky nang xa hoi. ((hieu va) or (lieu va)) nam thuoc va dan va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc sach) OR (hoc sach)) ky nang xa hoi. ((hieu va) OR (lieu va)) nam thuoc va dan va cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc sach) OR (hoc sach)) ky nang xa hoi. ((hieu va) or (lieu va)) nam thuoc va dan va cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((doc sach) OR (hoc sach)) ky nang xa hoi. ((hieu va) or (lieu va)) nam thuoc va dan va cuu tre*.