Perhaps you should try some spelling variations:
van chat » cao chat
va triet » va trien, ve triet, cua triet
vanh dai » van dai, vanh tai, lanh dao
va vanh » va van, va danh, va hanh
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
van cau » van dau, van hau, toan cau
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
tuc va » thuc va, truc va, tuc xa
ma hoi » mai hoi, xa hoi, ma hoa
thiet » thieu

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