Perhaps you should try some spelling variations:
dung tren » dung trong, dung trung
nang mai » nang ma, nang tai, lang mai
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ve cac » va cac, vien cac
luc va » duc va, tuc va, loc va

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 ky nang mai hoi. hieu ve cac luc va hanh vi ((((dua tren) or (dung tren))) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang mai hoi. hieu ve cac luc va hanh vi ((((dua tren) OR (dung tren))) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang mai hoi. hieu ve cac luc va hanh vi ((((dua tren) or (dung tren))) or (cuu tre))*.