Perhaps you should try some spelling variations:
vien cao » vien cac, vien dai, vien da
van nang » van quang, van ban, van dong
vien cam » vien cac, vien nam, vien can
sach van » sach han, sach va, bach van
xuc van » duc van, luc van, vuc van
hanh de » hanh ve, hanh kem
hanh di » hanh vi, hang di, danh di
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
cua tuc » cua duc, cua tu, cua thuoc

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 van nang xa hoi. hieu ((vien cam) or (vien cao)) xuc van ((hanh di) OR (hanh de)) cua tuc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach van nang xa hoi. hieu ((vien cam) OR (vien cao)) xuc van ((hanh di) OR (hanh de)) cua tuc.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach van nang xa hoi. hieu ((vien cam) or (vien cao)) xuc van ((hanh di) OR (hanh de)) cua tuc".
• Adding a wildcard symbol may retrieve word variants: tu sach van nang xa hoi. hieu ((vien cam) or (vien cao)) xuc van ((hanh di) OR (hanh de)) cua tuc*.