Perhaps you should try some spelling variations:
nang doc » nang luc
cham xuc » cam xuc, chat xuc, cham soc
cau tren » cu tren, dau tren, ca tren
doc hoc » duoc hoc, toc hoc, duc hoc
hieu ve » hieu va, hieu van
sach ky » sach y, sach ty, sach kem
hanh va » hanh vi
ve cham » va cham, ve chat, vu cham
sac ky » cac ky, sai ky
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) or (sac ky)) nang doc hoc. hieu ve cham xuc va ((hanh va) OR (hang va)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang doc hoc. hieu ve cham xuc va ((hanh va) OR (hang va)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) nang doc hoc. hieu ve cham xuc va ((hanh va) OR (hang va)) cau tren".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) nang doc hoc. hieu ve cham xuc va ((hanh va) OR (hang va)) cau tren*.