Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh dao » thanh dat, thanh dam, doanh dao
suu viet » su viet, sau viet, sieu viet
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
co tuc » co thuc, co tu, co toc
tuc va » thuc va, truc va, tuc xa
va co » vo co

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((nang xa) or (nang x)) hoi. hieu va co tuc va ((hanh dao) OR (lanh dao)) suu viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang xa) OR (nang x)) hoi. hieu va co tuc va ((hanh dao) OR (lanh dao)) suu viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((nang xa) or (nang x)) hoi. hieu va co tuc va ((hanh dao) OR (lanh dao)) suu viet".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang xa) or (nang x)) hoi. hieu va co tuc va ((hanh dao) OR (lanh dao)) suu viet*.