Perhaps you should try some spelling variations:
thien van » thi van
sach thu » sach thue, sach thieu, sach tham
thuc dan » thuc hanh, hoc dan, thuc vat
hanh va » hang va, hanh vi
van cam » van nam, van lam, van cau
sach ty » sach y, sach tu, xach tay
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) OR (sach thu)) lang xa hoi. thien van cam ((tuc va) or (thuc dan)) hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) lang xa hoi. thien van cam ((tuc va) OR (thuc dan)) hanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach thu)) lang xa hoi. thien van cam ((tuc va) or (thuc dan)) hanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach thu)) lang xa hoi. thien van cam ((tuc va) or (thuc dan)) hanh va cua tre*.