Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
va triet » va thiet, va trien, ve triet
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va thanh, va danh
ma hoi » mai hoi, xa hoi, ma hoa
ve cac » vien cac
cua tu » cua tuc, cua su, cua cu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ty nang ma hoi. hieu ((va cac) or (ve cac)) duc va hanh vi ((cua tu) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ty nang ma hoi. hieu ((va cac) OR (ve cac)) duc va hanh vi ((cua tu) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: doc sach ty nang ma hoi. hieu ((va cac) or (ve cac)) duc va hanh vi ((cua tu) or (va triet))*.