Perhaps you should try some spelling variations:
dao tren » dat tren, dao tien, dau tren
van hanh » van thanh, ban hanh, van anh
nang doc » nang luc
vu cham » va cham, vu kham, tu cham
hanh va » hang va, hanh vi
luc van » luoc van, luu van, duc van
ve cham » va cham, ve chat, ve chim
doc hoc » duoc hoc, toc hoc, duc hoc
su sach » so sach, vu sach
y nang » ky nang, ly nang, v nang
va dao » ca dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu hoach) or (su sach)) y nang doc hoc. hieu ((ve cham) or (vu cham)) luc van hanh va dao tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu hoach) OR (su sach)) y nang doc hoc. hieu ((ve cham) OR (vu cham)) luc van hanh va dao tren.
• Adding a wildcard symbol may retrieve word variants: ((thu hoach) or (su sach)) y nang doc hoc. hieu ((ve cham) or (vu cham)) luc van hanh va dao tren*.