Perhaps you should try some spelling variations:
vu khanh » vu thanh, van khanh, duy khanh
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
ve cac » va cac, vien cac
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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) or (vu khanh)) ky nang xa hoi. hieu ve cac nuoc va hanh ((vi cua) OR (di cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu khanh)) ky nang xa hoi. hieu ve cac nuoc va hanh ((vi cua) OR (di cua)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (vu khanh)) ky nang xa hoi. hieu ve cac nuoc va hanh ((vi cua) OR (di cua)) triet*".