Perhaps you should try some spelling variations:
phap nuoc » nha nuoc, cap nuoc, phap hoc
hac nuoc » hoc nuoc, cac nuoc, nhat nuoc
dang tri » dang thi, dung tri, dong tri
van dang » van dong, van dung, van nang
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
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: thuat ((sach ky) or (sach y)) nang xa hoi. hieu van ((hac nuoc) OR (phap nuoc)) van dang tri cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach ky) OR (sach y)) nang xa hoi. hieu van ((hac nuoc) OR (phap nuoc)) van dang tri cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach ky) or (sach y)) nang xa hoi. hieu van ((hac nuoc) OR (phap nuoc)) van dang tri cua tu".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach ky) or (sach y)) nang xa hoi. hieu van ((hac nuoc) OR (phap nuoc)) van dang tri cua tu*.