Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
sach tu » sach thu, cach tu, sach uu
nang ho » nang hoc, nang co, tang ho
sach ty » sach y, sach thu, xach tay
lam duc » lam duoc, pham duc, nam duoc
hanh de » hanh ve, hanh kem
hang di » hang doi, hang vi, hang dien
hieu va » lieu va, hieu qua
ho hoc » hoa hoc, cho hoc, hoi hoc
va lam » van lam, va lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((sach ty) OR (sach tu)) nang ho hoc. hieu va lam duc va ((hanh de) or (hang di)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach ty) OR (sach tu)) nang ho hoc. hieu va lam duc va ((hanh de) OR (hang di)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach ty) OR (sach tu)) nang ho hoc. hieu va lam duc va ((hanh de) or (hang di)) su triet".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach ty) OR (sach tu)) nang ho hoc. hieu va lam duc va ((hanh de) or (hang di)) su triet*.