Perhaps you should try some spelling variations:
su sach » so sach, vu sach
doi cua » dai cua, hoi cua
va hanh » van hanh, va thanh, va danh
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
ty nang » ky nang, ty hang, ly nang
luc va » duc va, tuc va, loc va
di cua » dai cua, de cua, do cua
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: su sach ((ty nang) OR (ty xang)) xa hoi. hieu ve cac luc va hanh ((di cua) or (doi cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty nang) OR (ty xang)) xa hoi. hieu ve cac luc va hanh ((di cua) OR (doi cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) OR (ty xang)) xa hoi. hieu ve cac luc va hanh ((di cua) or (doi cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty nang) OR (ty xang)) xa hoi. hieu ve cac luc va hanh ((di cua) or (doi cua)) tre*.