Perhaps you should try some spelling variations:
phan duc » pham duc, phan tu, phan dau
kiem sat » kiem soat, giam sat, kiem va
lang van » dang van, tang van, hoang van
kiem su » kiem thu, kiet suc
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
ve phan » va phan, ke phan, ve phat

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 y ((nang xa) or (lang van)) hoi. hieu ve phan duc va hanh ((kiem su) OR (kiem sat)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (lang van)) hoi. hieu ve phan duc va hanh ((kiem su) OR (kiem sat)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) or (lang van)) hoi. hieu ve phan duc va hanh ((kiem su) OR (kiem sat)) triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (lang van)) hoi. hieu ve phan duc va hanh ((kiem su) OR (kiem sat)) triet*.