Perhaps you should try some spelling variations:
nuoc quan » nuoc luan, quoc quan, nguoi quan
benh hai » benh dai, benh tai, benh bai
sach ty » sach y, sach tu, sach thu
hai cua » thai cua, dai cua, hoi cua
xuc san » xuc ban, luc sang, nuoc san
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
va cau » van cau, va cac, va dau
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sac ky)) nang xa hoi. hieu va cau ((xuc san) or (nuoc quan)) benh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sac ky)) nang xa hoi. hieu va cau ((xuc san) OR (nuoc quan)) benh hai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sac ky)) nang xa hoi. hieu va cau ((xuc san) or (nuoc quan)) benh hai cua tre*.