Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hang dau » hang va, hang tai
dau cua » dai cua, day cua, cau cua
thuc va » thuc dan, thuc day
ve cach » va cach, ve cac, ve canh
hieu ve » hieu va, hieu van
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((y nang) or (ly nang)) xa hoi. hieu ve cach ((thuc va) OR (thuc vat)) hang dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((y nang) OR (ly nang)) xa hoi. hieu ve cach ((thuc va) OR (thuc vat)) hang dau cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ((y nang) or (ly nang)) xa hoi. hieu ve cach ((thuc va) OR (thuc vat)) hang dau cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((y nang) or (ly nang)) xa hoi. hieu ve cach ((thuc va) OR (thuc vat)) hang dau cua tre*.