Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
cac duc » cac du, cao duc, cac nuoc
san cua » sang cua, ban cua, dan cua
hieu ve » hieu va, hieu van
cac dac » cac dan, cac dai, cac bac
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((y nang) or (v nang)) xa hoi. hieu ve ((cac duc) OR (cac dac)) va thanh san cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y nang) OR (v nang)) xa hoi. hieu ve ((cac duc) OR (cac dac)) va thanh san cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y nang) or (v nang)) xa hoi. hieu ve ((cac duc) OR (cac dac)) va thanh san cua te*".