Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh tai » thanh tai, hang tai, han tai
sach ly » sach y, sach lo, sach ty
cuc tre » duc tre, cua tre, cuc thue
thuc va » thuc vat, thuc dan, thuc day
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
hang xa » hoang xa, hang va, hang ca
ly hang » ly quang
tuc va » truc va, tuc xa, duc va
ve cac » va cac, vien cac

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

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