Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
van chat » cao chat
ve chat » va chat
hanh va » hang va, hanh vi
loc van » luoc van, hoc van, lo van
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, ma hoa
va va » va van, va vua, va vai

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