Perhaps you should try some spelling variations:
trong hai » trong thai, trong tai, trong hoat
hieu vien » hieu hien, hieu viec, thieu nien
trong ha » trong nha, trong hao, trong hoa
tinh lap » trinh lap, tinh lao, dinh lap
va tinh » may tinh
cac dac » cac dan, cac dai, cac bac
cac duc » cac du, cao duc, cac nuoc
lap cua » lai cua, tap cua, lam cua
xac ky » cac ky, sac ky, bac ky
su xac » pu xac, su cac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su xac ky ((trong ha) OR (trong hai)) hoi. hieu vien ((cac duc) OR (cac dac)) va tinh lap cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su xac ky ((trong ha) or (trong hai)) hoi. hieu vien ((cac duc) OR (cac dac)) va tinh lap cua vat~".
• Adding a wildcard symbol may retrieve word variants: su xac ky ((trong ha) or (trong hai)) hoi. hieu vien ((cac duc) OR (cac dac)) va tinh lap cua vat*.