Perhaps you should try some spelling variations:
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
hoc may » hoc ma
voi cua » hoi cua, moi cua, coi cua
doi cua » dai cua, hoi cua
am hoc » ad hoc
va am » va lam, va cam

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 (su sach)) ky nang xa hoi. hieu va am hoc may tinh ((voi cua) OR (doi cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang xa hoi. hieu va am hoc may tinh ((voi cua) OR (doi cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang xa hoi. hieu va am hoc may tinh ((voi cua) OR (doi cua)) tre*".