Perhaps you should try some spelling variations:
lang van » dang van, tang van, hoang van
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di 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 ly ((lang xa) OR (lang van)) hoi. hieu ve cam ((tuc va) or (thuc vat)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly ((lang xa) OR (lang van)) hoi. hieu ve cam ((tuc va) OR (thuc vat)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly ((lang xa) OR (lang van)) hoi. hieu ve cam ((tuc va) or (thuc vat)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ly ((lang xa) OR (lang van)) hoi. hieu ve cam ((tuc va) or (thuc vat)) hanh vi cua tre*.