Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
hanh va » hang va, hanh vi
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
xang xa » lang xa, mang xa, ang xa
xuc va » duc va, tuc va, luc 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: tu sach ty xang xa hoi. hieu ve cac ((xuc va) or (truc va)) ((dung tai) or (hanh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty xang xa hoi. hieu ve cac ((xuc va) OR (truc va)) ((dung tai) OR (hanh va)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty xang xa hoi. hieu ve cac ((xuc va) or (truc va)) ((dung tai) or (hanh va)) cua tre*.