Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
luu tre » cuu tre, luy tre
truc va » thuc va, thuc vat, trung va
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
ly nang » ky nang, ly hang, ly vang
ve cac » va cac, vien cac
ma hoi » mai hoi, xa hoi, ma hoa

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 nang ma hoi. hieu ve cac ((duc va) or (truc va)) hanh vi ((luu tre) OR (luu tru))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly nang ma hoi. hieu ve cac ((duc va) OR (truc va)) hanh vi ((luu tre) OR (luu tru)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly nang ma hoi. hieu ve cac ((duc va) or (truc va)) hanh vi ((luu tre) OR (luu tru))".
• Adding a wildcard symbol may retrieve word variants: su sach ly nang ma hoi. hieu ve cac ((duc va) or (truc va)) hanh vi ((luu tre) OR (luu tru))*.